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Spring suspension question


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By AggregateDood - Saturday, July 09, 2011 4:16 PM
I'm restoring a 1962 351 model Pete and am tackling the rear ends first. Everyone tells me I need to air ride it, but I intend on restoring the truck in a more vintage style. The truck has a Hendrickson Walking Beam.

I would like to install:

- Reyco 4 leaf with torque rods: I'd like to improve the ride but keep axle wrap-up to a minimum with good traction and have been told that a Reyco 4 spring would be a good choice.
- Eaton 402's
- Highway gears (3.55:1): I won't be making a living with the truck, most miles will be on the freeway going to truck shows

I found a frame "cut-off" at Valley Truck Parts in Fresno CA that had exactly that, but it sold right before I got the money together, so I am looking for another. As I look for another one there is always one thing that isn't what I want, such as having SQHD's or Peterbilt 4 leaf instead of Reyco etc...

So my questions are,
- can anyone give me any input on how 70's vintage Peterbilt 4 leaf compares to Reyco (or are they the same)? Is the 4 spring and torque rod set up my best choice for antiwrap up design and decent ride? Are there any other rear suspensions that I should consider that won't overly modernize the truck?

- As SQHD's evolved, are there models that are the equivalent of Eaton 402's, are there SQHD's to stay away from and others that are desirable?

The style I am trying to create is as a vintage heavy equipment hauler/end dump, low bed ramps, day cab with head ache rack, 335 Cummins with 5x4 trans etc... but with a ride that will get me to the show in one piece.
By Aaron - Saturday, July 09, 2011 5:45 PM
SQHD's with the 12 bolt axle would have been used at that time for that work, thats almost all there was.  Nothing wrong with them they did the job for years and drop ins are fairly inexpensive.  For CA running 3:90's would do  you a nice job, even 4:11's topped out in 13 th  will do you 75.
By John_Costley - Saturday, July 09, 2011 11:15 PM
Just my opinion, but I would convert that Hendrickson to extended leaf, RTE, which is easy and cheap to do and rides very well when empty or bobtail.RTE is an option over standard RT, though Im not sure how early it was availible, its not likely most nitpickers would notice if you converted.If youre not familiar with RTE, take a look at page 3  http://www.hendrickson-intl.com/pdfs/Truck_PDFs/Rt/45745-137.pdf

Another altenative would be to convert it to air ride while retaining the walking beams, though its alot more expensive than an RTE conversion  http://www.raydanmfg.com/?page=about&section=whyAirLink

Hard to beat walking beams for a combination of articulation plus torque control.I would never purposely convert to any 4 leaf suspension, thats like a self inflicted wound.The only thing 4 leaf has going for it is that its cheap and light, other than that it handles and rides like crap, but thats just my opinion.If someone gave me a truck with 4 leaf the first thing I would do is cut it off and scrap it.You cant give away a 4 leaf cuttoff up here.

Nothing wrong with SQHDs and you can get 3:55s if you want, though 3:70s would be easier to find.John
By peterj - Sunday, July 10, 2011 12:11 AM
The RTE isn't bad for an empty trailer, but still to stiff for bobtail. One guy who dropped a lot of heavy job trailers, cut one leaf out of the extention and add the shock mount kit. It did a good job bobtail, and no loss of capacity for job .....

The first one we had was 68'
By wayne graham - Sunday, July 10, 2011 4:56 AM
I had a 69 with extended leaf so I know they went back that far but they were almost as miserable . I have a pete on pete 4 leaf and it rides about the same as rayco-not good. They are selleng air-ride cut-offs for a song these days and they work so well that I would not invest any time or money in any spring set-up. As long as you stay with a low-leaf design any late model system will work fine. We are installing a volvo air ride on a pete cause it is a nice low profile suspension. All the low leaf are basically the design that Hendrickson used to start the whole thing. They ride good and are low maintenance. I have a 4 axle pete with low leaf that has done heavy haul for over one million miles and it holds up fine. If you decide to go air suspension do not let anyone try to sell you Pete air-track or KW 8-bag as you will notice no improvement over walking beams. Now all of this is strictly the opinion of an old man and may or may not help you but here it is and you did ask. HA-HA Wayne
By dclerici - Sunday, July 10, 2011 5:01 AM
Hutchens also made a 4-spring susp that was popular in the time frame that you're talking about.
By wayne graham - Sunday, July 10, 2011 5:12 AM
Daveas far as I can remember Hutch was a trailer suspension for the most part however I could be wrong as usual. Wayne
By Geoff Weeks - Sunday, July 10, 2011 5:23 AM
You didn't say what kind of walking beam you have, spring?, rubber pad? Before I went thru the trouble of changeing I would see what I had. Have you ever run a walking beam suspension? Are you baseing your choice on other peoples critisims of the walking beam? I have a IHC Fleetstar with the plain-jane walking beam spring, no extra torque rods, no extended leaf. It has a very short wheelbase which should make it ride like crap, but it doesn't. A good frost-heave will launch you a bit in the seat, but that is true for just about any suspension.  Before I'd rip that out of there, I'd pull the springs, inspect the spring pin bushings and pin, and dis-assemble the sping pack, and re-paint the spings, not much money and will make it work a whole lot better.

  4 spring was the cheapest, lightest suspension around, still is, but that is all it has going for it. No heavy-hauler would spec it, it doesn't have the travel needed for off-road, or heavy haul RGN type work. It is a fair on-hiway suspension.

 You could save yourself a whole lot of money that could be used elsewhere in the restoration if you left the suspension alone and kept the rears you have, may be exchangeing the drop-in for a ratio your more comfortable with.

  All this goes out the window, if you are streching or modifiying the frame.

  I just purchesed a walking beam cut-off to REPLACE the air ride on my road tractor! With a long wheelbase the walking beam should ride good. I know even on the shortwheel base  Fleetstar it rode good with a load.

  402's aren't period correct (nothing wrong with that in my opinion) and are now obsolete themselves. A good diff but it seams anything Eaton has a primimum price.

  I recently drove a 4 spring tractor on a test ride with somebody, the slightest uneven ground and I was reaching for the powerdivider lock.
By Geoff Weeks - Sunday, July 10, 2011 5:25 AM
wayne graham (7/10/2011)
Daveas far as I can remember Hutch was a trailer suspension for the most part however I could be wrong as usual. Wayne


 I think Rayco and Dayton were big names in four spring tractor suspensions, and of course each  truck mfg also had a "corp 4 spring" which was often one of the two above with the truck makers name cast into parts.
By Geoff Weeks - Sunday, July 10, 2011 6:01 AM
wayne graham (7/10/2011)
If you decide to go air suspension do not let anyone try to sell you Pete air-track or KW 8-bag as you will notice no improvement over walking beams. Now all of this is strictly the opinion of an old man and may or may not help you but here it is and you did ask. HA-HA Wayne


I would add the Neway ARDAB (air beam) to that list also, not to be confused with the ARD suspension which is a good suspension but heavy.
By curdog - Sunday, July 10, 2011 7:53 AM
I'm with you Geoff. The Hendrickson spring walking beam on my truck actually rides pretty good I think bobtailing at 162" wb. I'm going out to 225" with a donor truck and double framing, but I'm keeping the Hendrickson. Need the traction. 

Last year I was running a dump truck with the Reyco 4 spring and it was absolutely helpless off the pavement.
By AggregateDood - Sunday, July 10, 2011 9:05 AM

Thank you for all of the replies, you have all given me a new perspective and reconsideration of the walking beam. A lot of my previous advice was from a co worker/friend (who sold me the truck) who, although trying to be helpful, has in the past, given my some questionable information.

I have a machine shop background and limited engineering and prototyping experience and own a small street rod fabrication/hobby shop. As I stand back and take a longer look at walking beams, the action/reaction design of the pivoting beams are much more obvious. With respect to traction, I can now see how each wheel would want to follow the ground's contours. Previously I had only viewed it as a huge source of un-sprung weight with a railroad locomotive sized spring that would cause the truck to skip over the tops of every contour of the road.

I now see the suspension as a separate upper and lower assembly:

-The lower pivoting beam assembly is what rolls over and follows the road's contours and provides traction.

-The upper spring and mounting assembly needs to be sprung and dampened to suit the overall driving application.

The solution that I now have etched into my brain is the Raydan air bag walking beam assembly that John Costly linked me to.

http://www.raydanmfg.com/?page=about&section=whyAirLink

If the upper mount, trailing arm and air-bag assembly is compatible to my lower beam assembly, or can be machined, welded or otherwise fabbed to match up, then I will have married the old world to the new, and kept the most visible parts of my truck looking vintage.

This is how I approach building street rods and muscle cars. I see people all the time, throwing away valuable vintage hardware because they don’t see the potential in it once rebuilt and or otherwise modified to suit the driving need. So they end up with a car built from a catalog of modern parts that has no soul and reduced nostalgic desirability.

Thanks,

Tom Clark

Here are some pictures of the truck

By wayne graham - Sunday, July 10, 2011 9:22 AM
I certainly admire your perspective of all things mechanical and I too am one of the last to throw away anything and love the older the best. I wish you yhe best of luck .  your understanding of that suspension is dead on when the truck is loaded heavy. the heavier it is loaded the better it will ride. HOWEVER WHEN IT IS EMPTY OR BOB-TAIL IT WILL DO WHAT YOU ORIGINALLY THOUGHT . That is to say it will hit the tops of the bumps as the front axle hits yuo will receive a jolt then before you land all the way down in  the seat the back axle will hit and let the seat back whack you real good. We always called it air ride cause the truck and the driver were both in th air most of the time. either on the way up or down. So if you are going to be loaded heavy all the time it is a good set up. Just trying to say analyze it all real good before you do anything cause all of it is a lot of work and money. Good luck and I will be quiet. Wayne
By Geoff Weeks - Sunday, July 10, 2011 10:31 AM
The "name of the game" in any tandem suspension is transfer of weight front to back while going over rough roads, Much of the dampining is from this transfer, more then the springs, (air, steel or torsion bar) which are slow to react  to the impulse. Springs come into place at the slower rise and fall of the road.  The walking beam does a good job of transfering the load front to back. There are high freq and low freq occilations and different type of isolation is required for each. Air is better at high then most other,but still lack some low freq dampining which is why many "air ride" use some sort of steel spring and an air bag at the back of it. (Hendrickson air, Volvo, Mack, IHC corp air  etc) pure air on a swing arm requires longer stroke bags with some sort of variable rate "piston" to achieve the same result. One need only to look at the 8 bag KW to see all air isn't the way to go. To look at it another way, The truck already has air ride... they are called tires, and they don't do a great job dampining out the bumps.

 I think the Hendrickson Air ride (or one of the Corp knock offs) are about the best in a air ride, enough travel to be smooth, without relying solely on an air bag to do all the dampining. It sole weakness is the rate of forward and back transfer which is dependant on the air line between the bags.

Keep in mind, back in the day, likely ment short wheel base on roads that were less then ideal. There is a world of differance between today and the 70's in terms of type of road, and wheelbase both of which have a large impact on ride quality.

If you are planing to keep that wheel base, I think you should have a good rideing truck regardless of what suspension you decide to run.
By wayne graham - Sunday, July 10, 2011 11:11 AM
Forgot to tell you that is the makings of a real nice Pete. I had a 69 and have always liked the unilite cab. Good luck and keep us posted as we love to watch these things progress. Hope we did not get to detailed on the suspension thing but we are serious about telling you all we can and giving our honest opinion. Hope to have been of some help to you sir. Wayne 
By dclerici - Sunday, July 10, 2011 11:58 AM
Hutch did and still does mfg a tractor 4-spring susp. Back in that time era the local quarry had them on the Pete and KW end-dump and transfer chassis as the Pete 4-spring (and maybe the Reyco 101, can't recall) would fall out of the center saddle if in too much articulation.

The walking beam with (if RT) shocks does produce a good ride empty.

Reyco does offer a 4-leaf taper spring and used to offer (don't know if they still do) a single leaf graphite composite const in the 102 4-spring. That was mainly for weight and I would think that the ride would be about the same as the steel spring packs.

I had Reyco 102 on a '79 Pete transfer and it rode pretty rough empty on the concrete sectioned freeways.
By John_Costley - Sunday, July 10, 2011 11:58 AM
Tom,

That Pete has alot of potential.Old trucks are just like Hot Rods, its just that the parts and tools are quite a bit bigger, lol.

I've talked with a few experianced people that have done that conversion.They say it outperforms any other air ride they have ever driven, and they arent rookies.I'd like to try it myself some time just to see if the logic of the design comes thru to the reality of the road.

Raydan has been building that kit for over a decade.Hendrickson came out with their own kit 5-6 years ago and it is now availible as an OEM option.  http://www.hendrickson-intl.com/products/product_detail/ar2.asp  

The biggest differances are that Raydan uses a large center bag and smaller rear bag, they only require transverse rods though the original parralell rods can still be used for a four rod system, and they allow any application, tractor, truck, whatever.

With Hendricksons copy cat kit, they use two eqaul size bags per side, they require 4 rods (which is great for stabilty but limits articulation), and they only market and approve it for truck applications, not tractor.

Although Hendrickson has the big name recognition, they are playing catchup and dancing around Raydan's patent.The Raydan kit is just plain better.Just the bag difference alone warrants using Raydan over Hendrickson.That large center bag with a smaller overload bag is a night and day difference to Hendrickson's 4 bag approach.

If you want to save unsprung weight swap youre walking beams for a set of the optional aluminum ones.They are availible at junk yards or new, would have been optional on a new Pete back then.Very eye catching if sanded and polished, too eye catching for a stock appearing truck but nice for a custom, lol.When you buy replacement drop ins to change ratios you can also get the optional aluminum cases, big chunk of weight there.If you want to change the way the suspension reacts to sharp/quick bumps you can changes the leangth of the beams and increase the spacing between youre drive axles.The longer the spacing, the better the traction and ride.John
By AggregateDood - Sunday, July 10, 2011 12:08 PM
I am very grateful for all the help and don't worry about getting too technical, if I don't know the meaning of a word or engineering concept, I look it up and learn it. People usually tell me I think too much, lol. I now have a better grasp on the front/rear weight transfer effect and that the movement of the beam lowers the shock impulse on any given wheel. Or in other words the beam yields to the load. I am also much enlightened about the false notion I had that a 4 spring set up can make good traction. I should know this because my last boss was not much of an expert at spec'ing equipment and my short wheel base air ride (Pete air track) end dump truck was so short on traction, even with the powerdivider locked, that I wished I had cross locking diffs. But I could go on all day about how underspec'd that truck was lol.

Geoff, when you mentioned Hendrickson's weight transfer shortcoming due to air bag equalizing, are you talking about their Primaax style with the 4 trailing arms? My thoughts are to run the AR-2 air and walking beam set up and in that case, the weight transfer is through the beam since all 4 bags are mounted to a common trailing arm (pair).

Wayne, the truck will get a bow tie visor, glass marker lights with the middle two cab lights being green like back in the day, a set of tube type Alcoas (I have a pair of 5 holes and a pair of 10 holes, if I find another pair of 5's they'll go on the back, if I find another pair of 10's the 5 holes will go on the front), rear quarter fenders and vintage style rear flaps and brackets and a grill bug screen and bumper mounted guard.  I have a new set of Dynaflex 5" straight stacks, brackets and Y pipe and a narrow aluminum front bumper. One thing though, the cab door corners are cracked and reinforced with steel plates to the point where the cab needs to be stripped down to the skeleton and completely rebuilt, the hood is in poor shape too, so I found another cab and hood from the same era that need one tenth of the amount of crack repair. So what I'm gonna do is restore the cab and hood in my shop and then when they are both complete I will drive the truck over and do a core exchange. I'm going to school for an HVAC certificate, so that oughta help me to get the vintage roof mount AC system restored and operational. Being that the cab and hood are going to be replaced, I am toying around with fabricating an ext hood and moving the cab back, just for the added "looks like it means business effect."

I have a You Tube page of me driving the above mentioned traction challenged end dump
http://www.youtube.com/user/AggregateDood?feature=mhum

Tom

Here is the core cab and hood:
By Geoff Weeks - Sunday, July 10, 2011 12:39 PM
AggregateDood (7/10/2011)
Geoff, when you mentioned Hendrickson's weight transfer shortcoming due to air bag equalizing, are you talking about their Primaax style with the 4 trailing arms? My thoughts are to run the AR-2 air and walking beam set up and in that case, the weight transfer is through the beam since all 4 bags are mounted to a common trailing arm (pair).

:


No, I was talking about the old HAR with the big Z spring and the bags on the back.  IHC used a version for their corp air ride until recently, now the fit something that looks like Freightliner's air liner suspension.

  There are many good suspensions and I don't think there is one that is best, esp 'cause there is different requirments for different type of trucking.

 I wouldn't rule any out (with the poss execption of the old western unit or the 8 bag KW) but look to how they work and decide if it is what you want.

  It seams everybody and their brother stuffs a Pete air-leaf under any convarsion but I haven't been all that impressed with the Pete I drove.

  Around here you don't need to be certified to work on 134a, and I would recomend converting to that as there is really no option. A manual hose crimper is nice but not cheap. I've never regreted buying mine.
By John_Costley - Sunday, July 10, 2011 1:05 PM
Tom,

Couple custom extendeds.If you do it right it can look close to stock, but Owner Operators have been modifying trucks for as long as there have been trucks so dont worry about keeping it stock.Modified trucks are part of trucking history and we dont have many pebble beach types in our hobby anyway,lol.Not sure if the black daycab is custom extended or just on a late model chassis.If its extended then its done right.John
By AggregateDood - Sunday, July 10, 2011 2:04 PM
Geoff Weeks (7/10/2011)
It seams everybody and their brother stuffs a Pete air-leaf under any convarsion but I haven't been all that impressed with the Pete I drove.
Around here you don't need to be certified to work on 134a, and I would recomend converting to that as there is really no option. A manual hose crimper is nice but not cheap. I've never regreted buying mine.
That's another reason I didn't want to do Pete air suspension, its like going to the hot rod shows and looking at row after row of '34 Fords on Mustang II front ends, gets boring. I want to see nostalgia rods and cars that wear their history, same with trucks. As for the AC, I just need to make sure I am running compatible compressor oil for the refrigerant (and hopefully the compressor will be compatible to the oil I need to run) per my HVAC teacher's advice...



John_Costley (7/10/2011)
Tom,

Couple custom extendeds.If you do it right it can look close to stock, but Owner Operators have been modifying trucks for as long as there have been trucks so dont worry about keeping it stock.Modified trucks are part of trucking history and we dont have many pebble beach types in our hobby anyway,lol.Not sure if the black daycab is custom extended or just on a late model chassis.If its extended then its done right.John
Thanks John I have some video of the National Convention that happened last year in Pleasanton CA on the You Tube page link from my last post. I really like the look of that black day cab and the green one, but probably won't get so carried away with the louvers, lol. My understanding is that the factory moved the cabs back 7" for the ext hoods? I gotta look and see if moving the cab mounts back will interfere with anything else, and what to do about the shifter linkages.
Tom
By Geoff Weeks - Sunday, July 10, 2011 2:21 PM
Almost all A/C back in the day were the 2 cyl York or Tecumsah and you change the oil to Ester or Pag. Both are avaiable in different grades. There is one compatable for what ever compressor is on there. There was some use of the Delco A-6 (a very good compressor) also.

  The biggest concern is condenser size, R134a needs more area to transfer the heat then R12 did. BTW they still make roof mounts, but they look different then the old ones.
By JeffLipinski - Monday, July 11, 2011 8:34 AM
Your donor cab looks pretty decent, just a bit better than mine was, and less moldy. I noticed the cowl lip on your original cab is gone, hopefully your donor cab is better there as well. Mine was bad on the radius (straight part was fine), had a heck of a time getting the curve right and not having the leading edge sticking up. If you want to go long hood, I know a guy who started with blank frame rails, used his original rails as "patterns" and moved the cab back 10", then made his own hood sections. Plenty of room for a 3406 air to air. You have enough frame rail, would only take 7 holes on each side to move the cab back.

What transmissions are in your truck? I noticed the second stick. And the air ducts in the top of the dash. AC is next on my list.
By JeffLipinski - Monday, July 11, 2011 8:36 AM
I would also keep the walking beams. With the aux do you need higher ratio rears?
By AggregateDood - Monday, July 11, 2011 8:40 PM

JeffLipinski (7/11/2011)
I noticed the cowl lip on your original cab is gone, hopefully your donor cab is better there as well. Mine was bad on the radius (straight part was fine), had a heck of a time getting the curve right and not having the leading edge sticking up.

What transmissions are in your truck? I noticed the second stick. With the aux do you need higher ratio rears?

Yep, the cowl is just one more thing on the original cab that makes it in need of being stripped down to the skeleton and re-skinned. The donor cab needs cowl work too, but not nearly as bad. Right now it has a 13 and a 4, but I would like to swap to a 5 main box. I'm open to the possibility of installing a 6 spd main, if anyone has any input on that (hmm input, no pun intended). Although I won't be working the truck, I would like to find a pair of twin countershaft boxes, just to equip the truck with all the bells and whistles. That would be consistent with the heavy haulage theme I am trying to create. When I previously talked about gear ratios, it was because I was intending to slide all new running gear under the truck, in which case I needed to decide what ratios to look for. Now things are changing.

The below picture is of a book that I bought just prior to getting the extra cab and hood. Notice the similarity of the truck in this picture to my cab on a previous post. I showed the book to the guy who gave me the cab. He did a double take and said, "yep, it was from that same company over in the San Joaquin Valley, it even had the striped bumper. Such a strange coincidence, it makes me think I should repaint it back to the same paint scheme.

By gulalastbilen - Wednesday, July 13, 2011 1:05 AM
Not hijacking this tread, only intrested in your opinion about aluminum frames.

Have a 359-70 with factory built Pete air susp(not air trac) and a wheelbase of ~210. I think that this set up has a bad traction, very stiff frame and little play on rear axles, the ride is quite hard to (not refferring to vibrations on other tread), every bump hits you twice from rear axles?

Expirence with european trucks and 4 bellow per axle is like decribed above, best way to get stuck!

Dan (in Sweden)
By wayne graham - Wednesday, July 13, 2011 3:57 AM
This is as I see it a matter of how much you want to spend. Replacing rails with steel is costly but the ultimate answer for the frame. Otherwise keep what you have and limit hole drilling. I assume you have pete air leaf which does not ride that well. Just like it's sister Air-Trac it does not oscillate very far. Maybe 3 inches. Pete low leaf will oscillate 7 inches which makes it far better for getting around job sites etc. Also air leaf will ride good with either frame. I use it on a 4 axle pete for heavy haul and it works great. mine is double frame steel so it is rigid frame also. Hope this helps. Wayne
By David M. Holt - Wednesday, July 13, 2011 4:47 PM
I couldn't agree more with John don,t waste you're time with 4 springer they ride terrible. If going to change cut off go air ride at least I'm  a Kw Guy so I'm probably a little bias. I driven about every suspension there is in the logging application. Ag 100 is my favorite the have there issues but ride the best in the woods a little tippy feeling  but don't look back it s not going anywhere. Not popular on this forum but very readily available.
By AggregateDood - Friday, August 05, 2011 1:37 PM
Update:
A rep from Raydan Manufacturing called me after my emailing them about local dealers. He was very helpful and talkative and has done an airlink installation on a '64 Kenworth show truck. He told me that I can purchase their retrofit kit and it will bolt up to the bushings of my existing beams. He also suggested I will have to install transverse torque rods, which they sell as a kit for about $600.00. He is emailing me product brochures and an application form for me to provide them frame dimensions etc. When I get the price I will repost. I just got a new job with better pay, which is perfect timing for me to be able to afford to stockpile parts for the restoration, so I'm getting pretty jazzed.
Next is to have reproduction wiring harnesses and a relay panel custom built by Courtland Truck Works.

A retrofit is shown about half way down this page.
http://www.raydanmfg.com/uploads/19162316814ac111d67358f.pdf

Tom
By Aaron - Friday, August 05, 2011 6:09 PM
You'll need two jobs now.
By JeffLipinski - Monday, August 08, 2011 10:18 AM
What do you need a relay panel for? I don't have a single relay in mine. You can reuse the curcuit breaker panel, just remove the old Klixon breakers, and replace them with the newer block type with the mounting bracket. Get a piece of brass strap 1/8" thick by 3/8" wide, drill holes to the correct spacing, and use it as a buss bar. Have one side (left or right) be the constant power stuff, other side be key on and accessories. Easy and WAY cheaper than having courtland make you something.