I converted 1956 to 4X4. Used 1980 front end. New springs in front. Shackle flip in rear. Reinforced front with inside C channel piece at motor mounts. 205 Xfer case.
Front spring was a Pro Comp (11411) 4" lift that fit the front diff. Fabbed a front hanger and used the 1980 rear shackle.
WOW!
that is a beautiful suburban... I'd love to see pictures of the suspension/underbody.
It looks like you are able to pull this frame modification off, but that doesn't mean that is a good idea. There are bound to be unseen unintended consequences. Something along the lines of "no free lunch".
What do you plan on doing with this truck?
A friend of mine had a '57 NAPCO which has the riveted on crossmember for the transfer case, indicating that it was set up by Chevrolet and not an add on kit. He drove it like he stole it. He went through several transfer cases and a transmission, but he did not have any issue with the front axle bottoming out. His truck came with extra leaves in the spring packs front and back.
Sounds like your buddy put a ton of miles on that thing, I'm hoping to do the same!
My mounts are also riveted (except for the front left leaf spring hanger), and I've got a 44x2" leaf spring with 6 leaves plus a tiny 7" long leaf that doesn't really count. The
specs say it's supposed to be 7 leaf on 4wd, but 6 on 2wd.
So far I've used the truck on a few roadtrip/offroad adventures around new mexico & colorado. Planning to do more of that in the future! It is extremely capable at low speed 4wd obstacles and has put a new Tacoma or two to shame! However, it's downfall is more average dirt roads with occasional rocks or washboards. This is where most of the non-highway driving occurs. I have to slow down to 10-20mph on roads where you'd normally drive 30 or 40. Airing down would help but I don't want to do that just to cruise some 2wd road.
You guys are right about beefing up the springs
it would be way easier, and that's how the truck was original. However, I'm spoiled enough to have a garage, and the problem is that even with saggy springs I still scrape the roof a little when I pull in without airing down. The burb is so ridiculously tall already that I'd hate to look down even farther at those other lifted bro-dozers, not to mention I'm also a knuckle brain once I get an idea.
The consequences I've thought of so far are:
1) Fender rubbing... however the measurements indicate this won't be an issue.
2) Oil pan clearance... I only have 2" down to the steering link. However I can get a 1956 oil pan where the sump is a little farther back. With a little hammer massage I should get another 2" no problem.
3) I did a little more research and I think the 'motion' ratio for my axle is about 2:1 for a single wheel bump... so I'll be pleased if I can increase my leaf spring compression travel from 1" up to 2 or 2.5" (ie. 4 to 5" wheel up-travel) so I'll be shooting for a notch between 1 and 1.5"
