55.2-59 55-59 suspension

[jeffs56]

Hey guys I’m still building my 56 Chevy truck. It’s getting close. But as time goes by I keep thinking about changing my front suspension. I’m currently using the dropped axle and front leaf springs in the front, with the disc brake conversion kit. I haven’t driven it yet. But obviously people tell me I’m nuts for using it cuz it’s going to ride and steer like crap. But that’s what I had. So I was wondering if I do decide to upgrade the front suspension. Would a corvette C4 suspension or a mustang 2 style be better. Thanks guys

[dsraven]

since you have the suspension in place try it out like it is, you might like it.

[dsraven]

since you have an upgraded suspension now you really should drive it like it is. maybe you like it, maybe you simply want to add power steering, maybe you find it has bump steer, some other issue or you simply don't like the ride. if you want to upgrade at that point then look into something that bolts in since then you would need to do less tearing apart of peripherals. a weld in IFS would be best to have the engine removed for cleaning and access to get good quality welds. some would want to remove the front body clip for access etc. that gets spendy unless you do that yourself. a bolt in could be done by a home guy. it really should have a frame check prior to any of that to ensure the frame is square, straight and not sagged.

[MiraclePieCo]

Having vast experience with lots of straight axle cars and trucks, I'm here to say the whoever told you it would ride and steer like crap is full of crap themselves. They repeat what they've heard but probably have very little actual experience with solid axle front ends themselves. Yes, old worn-out suspension will be awful to drive, but if your kingpins, tie rod ends, steering box etc are in good shape, an I-beam front end can ride and handle amazingly well. My '34 Ford PU was like a go-kart, just begging to be put through a slalom course. I had bias-ply tires on it too; I'd grown up with the assumption that radials handled better, but the stiff bias ply sidewalls made it feel like it was on rails! Finish your truck as is, enjoy driving it, and you'll have firsthand experience to silence the naysayers.

[mongocanfly]

But if by chance you want to swap out the solid axle for ifs in the future, then flatout engineering makes a very nice kit to use vett front ends...

[jeffs56]

I’m going to definitely finish it the way I’m building it now. Like you guys said I may like it. I think after seeing how it’s coming along I’m wanting to drive faster and take more corners lol. Not sure if a solid axle truck will hold up for that kind of driving. And I think the other issue I’m going to run into is my stock steering box. I don’t know if it’s good and I don’t know how to rebuild it

[_Ogre]

Originally Posted by dsraven

since you have the suspension in place try it out like it is, you might like it.

ogre agrees

Originally Posted by jeffs56

I don’t know if it’s good and I don’t know how to rebuild it

time to learn.

old box with all new suspension may be a waste of time, definitely rebuild or get it rebuilt
no straight axle drives as well as ifs, but big trucks are still built with straight axles
4x4 pickups don't corner or steer as nicely as the same model 2 wheel drive pickups

[jeffs56]

I can’t find anywhere to rebuild the steering box. Or videos or anything on how to rebuild it. I’m hoping it doesn’t ride that bad. But I’m definitely going to find out lol

[sack54]

Try Jim Carters has a kit and real good instructions. very easy to rebuild.

[mr48chev]

I'm going to say that unless the truck has been beat to death on rough roads and bouncing though fields or has a lot of miles on it the box is probably ok.

The main things with any I beam axle are

1. don't run excessively wide tires or deep reverse rims on the front.
2. make sure you caster and toe in are set right.
3. they have to be greased often as back in the 50's you had them greased every 1000 miles faithfully. There are guys on here who have actually never driven a vehicle with grease zerks in their lives and unless their granddad tells them about it they don't understand the need and then you get the guys who don't want a bit of grease getting on their spotless suspension pieces.

It's still what you are used to both ride and handling wise. If you drive a jeep CJ or older Cherokee with a solid axle you won't have a complaint. If you are used to Mercedes or BMW the handling won't make you happy and the ride might feel rough.

[jeffs56]

Yep there are a bunch of different opinions that’s for sure. The whole reason I’m thinking about changing suspension now is my buddy that puts on a few big car shows here locally. They are having a autocross course set up on there next big show in March of 2020. I’ve always wanted to try and do that. O just to go have fun. I know my solid axle can’t do it. So I thought I would change it now since I’m not that far into it. But being on a budget kills me lol

[RyanPartridge]

My straight axle truck handled like crap when I found it.
Slop in kingpins, worn out springs(sitting on bump stops), bad shocks, loud squeaky Toyota PS steering kit, super wide radial tires, etc...

After Sid dropped my axle 3" and did the kingpins, I installed new Posies springs(cut down the bumps stops), Bilstein shocks, front sway bar, new roller bearings, Coker classic Bias plys and swapped the Toyota PS kit for a rebuilt original stock steering box....you'd be in disbelief at how well the truck drives and handles. If you're ever in my neck of the woods I'll take ya for ride. It's so damn fun to drive.

Also...until recently it had 7" wide wheels all around. It now has 7" rears and 6" fronts and I was shocked at how much that improved the steering ease.

[dsraven]

like said here in other posts. the solid axle can drive well if:
-all the parts are tight within spec
-alignment is proper
-tire diameter is correct (affects the SAI-steering axis inclination or KPI-kingpin inclination angle)
-wheel offset is correct (affects the scrub radius which has a bearing on how the wheels will want to follow every crack in the road etc)
-stance isn't too far outta whack so front end gets loaded heavy and rear axle is light (no more than usual, lol)
-steering wheel is correct size (small wheel makes steering harder in low speed maneuvers)
-parts are lubed often, on a schedule, or an automatic greaser is installed. good quality grease is also a must.

yup, agreed. big trucks have solid axles and drive pretty well. they also don't get lowered, run with suspensions sitting almost on the bump stops, fatties installed on high offset wheels and a completely different tire diameter and different rake angles. they have leaf spring suspensions set up for the weight they carry, it is common to have auto levelling air bags out back to keep the rake angle correct (and thus the alignment correct) and the trucks are usually fairly long so easier to keep running in a straight line with minimal correction required. they also have power steering AND a huge steering wheel.highway trucks also usually get checked and repaired often as part of the legal requirement and will usually run an automatic greaser to keep things lubed properly. alignments get checked often simply due to the dollar value of a set of steering tires (not usually recapped like drive tires can be)

https://www.quora.com/What-is-king-pin-inclination

[Dan in Pasadena]

I'd also suggest you try driving it as you have it. If the kingpins have been redone to factory spec it'll ride, steer, handle better than 99% of the ones the guys that say it'll drive bad have ever driven.

I ALMOST put an MII kit in my '55. I even bought someone's unused Fatman Fabrications kit to install. Still have it gathering dust.

The guy that did my install does trucks all the time and recommended I switch to the Flat Out Engineering C4 IFS crossmember. Said they stay in alignment better and he preferred the handling much better. YMMV. I'm happy with mine.

[burnin oil]

Straight axles handle just fine but it is a different ride. They tend to have more body roll before digging in. I have had live axle 4x4s almost all my life and can't stand the new IFS systems. I think the ride is floaty and do not handle as well. They may not have the articulation for extreme four wheeling but they can handle exceptionally well on the street. The trick to driving them is to start laying back into the throttle halfway through the curve for a standard trans and slightly sooner for a auto or big cammed motor. The truck will go into a curve, body roll slightly, then the engine torque will plant it and launch you through the curve like you are on rails. I am not saying that IFS can't handle well but a straight axle isn't bad either. Truthfully around my neck of the woods I could probably out corner a vette, but that's because it would bottom out on our windy country roads. Although they are more jarring I prefer leaves to coil suspensions also. Leaves tend to be more stable and predictable throughout the travel. Coils, whether constant or variable rates, always seem wishy washy when asked to compensate for a large dip or pothole. Good luck and I am sure that you will enjoy the ride once you get a feel for it.

[1project2many]

I’ve always wanted to try and do that. O just to go have fun. I know my solid axle can’t do it. So I thought I would change it now since I’m not that far into it. But being on a budget kills me lol

I crewed a straight axle car at Limerock during a vintage racer day. We had to do a lot of jacking to set the car up but it handled well enough. With a purpose built car instead of a LH turn model we would have done better. Problem with the truck is front <-> rear weight distribution. Our trucks are around 80% weight on front axle. nfg.

If you can reduce the friction in the spring pack you will improve ride quality. Adding sliders and reducing the number of leaves helps. Shocks make a big difference and the wrong ones can ruin a lot of good work.

The steering linkage could be more robust. Play develops in the output shaft bushing of the steering box. The drag link is fairly solid but the curved steering arm at the back of the LH steering knuckle has a tendency to flex. This gets worse with radial tires or with wider tires. It also gets worse with more weight on the front axle. The OEM tie rod can flex as well. Changing to 1" tie rod, bracing the steering arm, and rebuilding the box can do wonders for the handling. Top it off with a sway bar and you'd be amazed at what the old girl can accomplish.

[jeffs56]

I’m glad there’s a lot of good positives about using the dropped axle and leaf springs. I’ve never driven a truck with one so I wish I knew how it was. I’ve only ridden in a 55 with a corvette suspension and I’m not sure if the coilovers weren’t setup right but seemed to stuff to me. I’m going to ride in a 57 with a mustang 2 next week. But I think I’ll get mine together the way it is and then if I don’t like it I can add a ifs. But I want to do everything I can to get it to ride as good as I can and reliable

[burnin oil]

I don't know for sure on these trucks but most manual steering from the 50s where Gemmer boxes. The 500 series was extremely popular by all the OEMs. I know these trucks have the front to back steering arm but to gemmer manual may be useful. They can be found online with some searching. The main reason I am posting this is that it's easier and cheaper to get parts for a Gemmer steering box than finding a kit marketed to a specific vehicle. The internals were basically the same with a case specific to the chassis
Even if the box isn't of the 500 series, I would be surprised if the internals wernt from Gemmer. Things like the sector shaft would be application specific but should use the same parts such as bearings and seals. Might not be the case here but you will find this tidbit helpful on other manual steering box rebuilds.