The Stovebolt Site Forums The Shop Area Driveline 56 3100 suspension question

Hi guys. My daily driver rides some pretty rough highways, lots of potholes and bumps on hard cement. My front end frequently bottoms out. I try to anticipate but sometimes don’t see it coming. Wondering what damage I’m doing. Any suggestions to dampen the impact. Stiffer shocks? Any suspension mod kits available? Any info appreciated.

Thomas,

In looking at the pictures of your truck in your Welcome Centre posts, it looks like your front suspension has been somewhat lowered from stock.

How about some closeup pics of your springs, shocks and the whole front axle??? They would offer a better chance for folks to understand what your set up is currently and how it might be adjusted/changed to counter the notorious "pot holes" of the NYC region (yes I have driven some of those roads visiting my son and his family on a few occasions and know just how bad they can be - LOL).

Dan

Hey Dan. Thanks for the suggestion. Here are a few pics. That profile is the current stance after raising the rear end back to original. Last pic is the rear.

Thomas,

Your front suspension has certainly been modified.

Your pics show only 4 leaves, where originally there would have been a minimum of 7 (8 if it was equipped with the heavy duty RPO front springs) - See screenshot below taken from the GM 1956 Chevrolet Truck data document).

Also of note is that it appears your 4 leaves seem to be rather "flat" - possibly de-arched to add to the lowering effect???

Your shocks looks to be "much shorter" than any standard replacement length shock length and to top it off, I see no rubber "bump stop". Probably removed due to the lowering process.

Your call on what you may want to do to remedy the situation, but my guess is you need to get some new springs and shocks (and bump stop) to restore original ride height and suspension travel.

Am sure others that have dealt with a similar situation will chime in and possible offer alternative solutions.

Let us know what you decide to do or if you have more questions.

Dan

All of that explains the Conestoga wagon ride quality.

Conestoga. Exactly. Thanks for the spec sheet. Thank God I'm retired.

Thats the first impression I got is that there is less leaves in the springs then it came out with. I believe the snubber mounts to the frame & contacts the front part of the spring. It probably is contacting the spring now. It looks like the upper shock bushing is wallerd out.
You need new front springs & shocks. It you wanted to get off easy you could get a spring co to make up some more leaves & add them to the spring with new shocks But the best way is to get new springs.

George

Wow. Thanks for the analysis. So I should not be surprised at this point that old cars and trucks need work but... Ouch. Any idea of cost and complexity of adding springs and upgrading shocks/bump stops. Are parts readily available? I'm ok with the stance but the ride is rough and I'd like to smooth it out a bit. So maybe not a return to original but at least replace those "flat" leaves and shocks?

All that stuff is available from Rock Auto.

Go to the website and have a look. I'll bet you can buy a new set of springs, bushings, and two new shocks for less than $500. And the best part is that all that stuff will just bolt on without any modifications necessary.

You're going to have to raise the stance if you want to improve the ride without totally customizing everything. The reason the ride is harsh is because there is no movement in the suspension. It needs to travel up and down.

New Dayton springs (bushings included) are $219 each and Monroe-Matic shocks are $16 each.

So that's $470 plus tax and shipping. If you buy them from Rock Auto, be sure and find a 5% discount code online.

Here's a current one. 239758575215047927

It'll save you $22 and keep the total with shipping just under $500.

Fantastic! Thanks.

Here's a picture of my '56 with stock suspension, I think the ride height looks good and it rides nice for a 1/2 ton truck that was built in the 50's.

Like others have said, if you want to maintain your existing height you'll need to open your wallet and get a custom front suspension system...

Mike B

@ Otto, Thanks for the info on Rock Auto. Never heard of the place but it is a parts paradise.

They definitely have the best organized website of any parts seller. I've found their prices are frequently much less than the local chain stores on certain items, especially for antique vehicles. Sometimes the shipping is a break even proposition, sometimes it still ends up costing less.

It's a great first stop for checking availability and prices. I always compare their prices with others, though because sometimes its cheaper to buy locally or even from one of the restoration houses.

Be sure and enter the discount code in the space where it says "How did you hear about us?"

@Mike B. Nice looking truck. I think I have to check my rear as well. Yours looks a bit lower than mine.

@Otto You list the leafs and the shocks, part numbers 22188 and 31000. Obviously you're familiar. What's the best way for me to find out my existing parts if I need replacement? Does a manual exist? GDads51 posted a spec sheet for the leafs. I'd like to get something like that.

I'm not sure I understand the question. I just order parts based on make and model and assume/hope the seller has the parts listed correctly. Most sellers don't use the original GM part numbers anyway.

If you need to know your original GM part numbers, someone will probably post a link to the GM master parts list shortly. I'm pretty sure I've seen somebody link to it on this site before.

For example, you chose Dayton over Dorman. Other than Dorman is out of stock, they seem identical. With my vintage VW, I usually choose German over Mexican parts,
they're usually better quality. So I guess, for my truck, my year, I could use either. Yes hopefully someone can post a parts resource. I want to be familiar before I order parts.

DAYTON 22188 Includes Bushings For Both Ends; 6 Leaf Info
Front

DORMAN 22188 Info
Front; 6 Leaf; 2 In. Spring Width; 1.75 In. Pack Thickness; 900 Lb. Average Capacity

These days it's a crapshoot when it comes to parts quality. You can't even trust brand names like AC Delco anymore as that stuff is junk made in China like everything else. Sometimes you get lucky like I did when I bought a water pump that turned out to be made in Japan. It looked like a piece of jewelry it was so nice.

I just posted those parts as an example. It wouldn't surprise me if the Dorman and Dayton products are made in the same factory. Who knows?

Sfizio,

Lots of vendors out there offering what you seek. It's all in how you search. No one source for parts info, but if you read below there is some good info to help you out.

The screen shot with the spring data was captured from the document I linked in my above reply, straight from the GM heritage Center web resource.

If you are looking for original GM part number info that will apply to your truck (1956 3100), check out some of my favorite resource links that cost you nothing but time!

- For a wide variety of access to free online publications including Shop Manuals, Parts Books and other related documents, check out the various links at Chevy Old Car Manual Project. I use this source on a daily basis.

- For a search engine more specific to finding "parts" info, I also use GMPartsWiki daily as well. This one takes a little "learning" to figure out what search info to use to get the best results, but once you learn how it can provide a treasure trove of original GM part number details and often help in searching for aftermarket replacement parts.

- On a more current search process, I often just use my preferred web search with the specific make/model/part info in the search to see what folks have out there for sale. You will find links to many of our usual reproduction & restoration vendors/suppliers, regular places like Rock Auto, NAPA, etc. as well as many used or NOS (New Out of Stock) parts being offered through eBay and other sources. Helpful hint - It often helps to include the original GM part number in your search if you can as many suppliers have built in cross reference indexes that will lead you to their current product to fill the need.

- You might also check out this post by member "Woogeroo" with a link to his Parts Vendors List for GM Trucks. Ton's of great info!!!

Looks like you might have a bit of reading on your to-do list - LOL!

Dan

Thanks Dan. Yes lots of reading but I love Rock Auto already. I’ve done this with my VW and have all my resources in place. Now I’m starting with Chevy. Way different car but the same process so once I get familiar I’m sure I’ll be fine.

There are several things you can do to improve the ride of your front end. The first is as George has suggested new springs and good shocks. You can also add a front sway bar, as well as helping with body roll a sway bar will also stiffen the front end a little. Making sure your steering linkage is tight and bushings are in good shape goes without saying.

@TUTS 59. Thanks. I’ll check a sway bar out as well. I had power steering installed and likely they went through the linkage at that point. The shop was supposed to install a modern suspension kit but could not. Apparently tight space. I like the idea of new leafs, shocks as well as sway bar if it helps. Need to see if I can do it myself. Shops get expensive as I sort this truck out.

Sway bar makes a difference in body lean during turns. It should make no difference (except a little increase in unsprung weight) driving straight. I have one and like it.

Front springs look flat. The previous owner of my 58 relocated the
short bottom leaf to the top in an attempt to lower the truck and that caused my truck to bottom out.
New springs will help. It stiffened mine up very nicely.

I’m hoping. Is this a big job? Hard to do? Scale 1-10.

I've done it on a Ford. It's not hard if the fasteners aren't rusted together. You need to have the wheels hanging free which means the truck has to be on a lift or tall jack stands.

Assemble everything loosely, lower the truck to put weight on the new parts to seat the bushings properly, then tighten up the bolts.

When I did the springs on my 46 I looked at all the vendors I could find, ended up going with Jim Carter/Oldchevytrucks.
Why? He has the springs made here in the US specifically to match the originals, on the 46 that meant the orientation of the eye is as original and the spring rate was correct to my truck. Was it the cheapest? NO. Did I want to do it twice? NO.
Did I have any issues or regrets? NO.

suppliers like Carter and Chevsofthe40’s are committed to doing their best to support us and our vehicles. I Try and support them back.

As an aside my truck ride height went up overall 2” since my orig springs were dead and flat.
Is it an easy job? 1-10 I say it’s a 3-4, it’s just parts changing but 2 reasons:
-springs are heavy and awkward and I work on my truck alone
-I had to section/cut out one of the seized bushings in the frame mount ( somewhat easy for me but PITA nonetheless).

I replaced every part I could, bushings shackles u bolts shock links/bushings etc.
It also changed the castor on my truck …..needed different shims and reset alignment.

Chuck

I used Eaton Detroit Spring when I replaced the front springs on my '57 1/2 ton GMC. What impressed me most about them was when the sales guy asked me which of the 4 different stock front springs I had on my truck, 6 leaf, 7 leaf, 8 leaf or 8 leaf with 4WD.

@Sfizio

Just replaced my springs a few weeks ago
order them off amazon and they came US MADE could not believe it.

Dorman 22-188 Front Leaf Spring Compatible with Select Chevrolet/GMC Models

Its not a big job did mine in about a half hour each and that was with me taking my time and a phone call.

Soak those ubolts good with pb blaster a few days in advance and it should come right off.
I even did mine with the tires still on the axle made it easier less jack stands. (one side at a time of course)
Check your shackles see if they need a replacement.

And go with the sway bar it really made a difference in my 56 as well.
Its a pretty easy install as well. Get a really good heavy drill and quality drill bits for a few holes in the frame. Again left the tire on and used it as a press on drill to keep a good steady push while slow drilling in the frame. Had a partner on that one just holding the steering wheel with steady pressure.

Make sure you replace the U-bolts, they are a one and done bolt as they stretch. When I need them I get them here...fast service and not very expensive.

https://www.uboltsdirect.com/

Mike B

@HCB3200. Amazon. Amazing. Yeah my big concern is with stuff not coming off because of rust. Being in a city where garage space is scarce, you can’t take a few days to get things done. It’s in and out so I always try to plan for that. @Mike B. Stretchy bolts but yeah. I like to replace as much as possible while things are apart. Really getting into doing this project. Tired of bottoming out on these bumpy Brooklyn roads. Some parts around here are totally commercial and rough and tumble. Dirt roads would be smoother.

The anti-sway bar can be a separate project. It doesn't have to be installed at the same time as the springs.

Also don't panic if it looks flat after you put them on. the fronts stock 900lb springs have a very small i mean very small arc when loaded.
But they ride fine if they are good springs on rough roads.

The ones you have are truly flat if not worse and not enough springs. Hence the bad ride.

Since you plan on replacing ubolts and possibly shackles and the springs. Remember if it does not come loose you can always cut the ubolts. Lots of shops just do that out the gate for speed. But remember lots of safety when doing that. After a few days of soaking them good. I just put a socket on with a long breaker bar got the loose rocking back and forth then zipped them off with 1/2 inch battery impact.
same with the rear spring mount bolt remember there is a nut on the backside AND its threaded on the inside. Take nut off first.
Also I would go with this style shackles up front gm switched to them in 57 for a reason. They work on 55-59 models as well as the older style on the 55-56 models. So you will see both kinds listed for all years on most sites.
I found my older style with just the center bolt actually got bent by the bushing shaft self threading itself to one side.

He can cut the U bolts but get ready for quite a "pop" .
If things are rusted bad, scale of 1-10 will be a 5.
Least for me.

Prob a good idea to split it up. Keep things simple.

Just did 2 sway bars. I had trepidations about it at first.
But by the 2nd it was down to a half an hour.
Battery drill, 2 different size drill bits and a white sharpie to mark the holes.
9/16ths wrench(2)

@guitplayer. Two away bars?! What happened? First one didn’t sway?

If the new sway bar you want to install is attached to the axle using the spring U-bolts, you should do it at the same time so you don't have to buy a second set of U-bolts...remember they are one and done.

Mike B

Hah...2 panel trucks. I also live in Brooklyn. Township.