Swap 1 ton suspension into 1500?

[fixmy59bug]

A while ago I bought a 73 C30 2wd 1 ton Suburban that has a good running gear and the body leaves alot to be desired. Just last night I bought a 89 GMC suburban 1500 1/2 ton. Considering I just picked up a set of Hummer H2 wheels for the 73, and the 89 is in MUCH better condition, I was thinking about swapping the 1 ton suspension into the 89 and mounting the H2 wheels. How difficult of a job would this be? Any custom fabrication I would need to do? I think the rear would be as simple as unbolting the springs, unhooking the brake lines and undoing the E-brake cables, and undoing the U-Joints. Am I right so far?

As far as the front goes, Would it be as simple as swapping springs, and steering knuckle assemblies (with brakes)? Or would I need to get nasty and do the control arms as well?

If anyone can shed some light on this, it would be very appreciated. Thanks.

 

[fixmy59bug]

Wow, this is kinda disappointing. Noone knows if this 1 ton suspension from my 73 Chevy 'Burban will swap into my 89 GMC 'Burban 1500?

 

[68on44s]

Both of them 2wd?

 

[fixmy59bug]

Yes, both of them are 2wd. The 89 is a GMC 1500 SLE suburban and the 73 is a C30 Suburban. What I want to do is transfer the 1 ton suspension from the 73 into the 89. I already have everything stripped out of the 73 now, I am wondering if I should be expecting any surprises.

 

[fixmy59bug]

I have been calling all sorts of places locally to find out if it would all work and so far noone has had any sort of concrete answer. One guy from a Chevy salvage yard even said "Well, those are different years, so no it won't work". LOL. Does anoyne in here have any sort of clue?

 

[Cricket]

Send a private message to SweetK30, he should be able to tell you. He has done some interesting swaps including solid axle onto IFS platform.

 

[55Willy]

1st off there is no such thing as a k30 sub, subs were only made in 1/2 and 3/4 ton set ups. yes the rear will swap right over springs and all.
the fronts you'll need to grab the a arms as the ball joints are different between them as well.

 

[fixmy59bug]

For sure the control arms will bolt right in? I know I will need the new control arms because the ball joints are bigger on the 8 lug and are not interchangeable. So I guess now is as good a time as any to change them. Will I need of the steering linkage? I have the complete 73 at my disposal.

 

[Eric M.]

yes the rear will swap right over springs and all.

Actually, the spring perches and shock mounts will be different from the 1 ton to 1/2 ton. The perches will need to be relocated unless you plan on swapping the hangers as well. The shock mounts on the 1 ton rear dif. will need to be relocated. E-Brake set up will be different from 73 to 89, driveshaft might be the right length. Don't forget your brakes. You might want to swap over the larger 1 ton master too.

I'm not sure about anything on the front of a 2wd.

Good Luck,

Eric M.

 

[fixmy59bug]

Well, the 1 ton suspension and the Hummer H2 wheels are now under my 89 1500 suburban.

It all went fairly simple. The main parts of the rear were a direct swap in. I swapped in the rear axle with the larger springs still attached. Luckily everything lined up perfectly. That's what I consider main parts. AS far as the drive shaft goes, the 1/2 ton driveshaft and 10 bolt rearend used smaller U joints than the larger 1 ton and 14bff. So I had to use the back half of the 73 drive shaft mated to the front half of the 89 drive shaft. That worked out perfect.

I also had to use the rear rubber flex line from the 73 as the 89 one was different threadding and slightly shorter. But I got the brakes in and bled and everything works perfect there as well. E-Brake cables are a different story all together. Right now I don't have one. The original 89 ebrake worked, but there was no possible way to attach these cables to the 73 rear brake hardware. So if I want a working E-brake again, I will have to wait until I take off the rear brakes and see how it all attaches. (the 73 ebrake was already disconnected, so I had no reason to pull the drums).

The front was a little more difficult. The lower control arms were a direct swap (including U bolts to hold it to the frame). The upper control arms I had to grind out the upper ball joints and bolt the new 1 ton ball joints in. I added the 1 ton springs, bolted up the steering knuckles and everything was good. Apparently the 89 1/2 ton and the 73 3/4 ton used the same calipers. So I didn't need to undo the brake lines on the front. Just reused the 89 calipers on the 89 knuckles.

I bolted everything together, added the Hummer H2 wheels and everything looks great. It requires a little bit of fender trimming on the front of the fenders because the tire rubs at the slightest turn. So that will be handles tomorrow. And I will make sure to get pics of the after product tomorrow.