another frame swap question truck on burb frame

[clear-lake-gmc]

i did a search but most results are for putting 67-72 cabs and beds on newer suburban chassis's but not much for the same era

i have also found that the 67-72 truck and burb frames are the same except for the rear of the burb is different?

i have a 71 gmc long bed stepside and found a 68 burb just trying to find out in detail what would have to be done body mounts moved etc

[Mike C]

There’s not much need for swapping a disc brake truck onto a drum brake Sub frame. One of the reasons for swapping on a newer Sub is you get a complete driveline upgrade.

Should be a fairly easy swap, but you won’t find many who have made it. Maybe a 68 truck on a 71 Sub chassis.

[clear-lake-gmc]

im getting the bare frame plus trailing arms so transfer all my parts over to it my frame has been patched at the steering box and the whole section behind the cab is rotted right through so the only reason for the swap is a solid frame.

moving body mounts isnt a big deal, and cutting some frame off the rear no biggy just trying to educate myself before i commit to buying it thats all

[dozerbill72]

The Burb frame is about a foot longer "all at the very back" and rear most cab mount and bed mounts is it. Very easy swap.

[Killer Bee]

don't quote me, I'm just a noob here, but some food for thought..

my understanding but please verify:

4x frames are narrower than 2x on trucks and suburbans

4x engine mounts are set back further than 2x

long bed truck and suburban frames are 127" wheel base

longhorn truck frames are 133" wheel base

ETA - read in here recently suburban and longhorn were same but after consulting my spids, they are not..

not sure about truck cab/bed vs suburban body mounts..

should be threads in here, hopefully those in the know will give you a nudge..

good luck!

[72chevynut]

I'll add a little of my knowledge. The 67-72 suburban wheelbase will be same as the long bed 67-72 pickup, 127". Your front clip and front cab supports should match up on the suburban frame. Behind that you will need to modify the body mounts. I myself would try to find a 69? 70-72 frame due to the 68 probably doesn't have the power steering box, frame indention and steering components.

[clear-lake-gmc]

Originally Posted by 72chevynut

I'll add a little of my knowledge. The 67-72 suburban wheelbase will be same as the long bed 67-72 pickup, 127". Your front clip and front cab supports should match up on the suburban frame. Behind that you will need to modify the body mounts. I myself would try to find a 69? 70-72 frame due to the 68 probably doesn't have the power steering box, frame indention and steering components.

yes i believe the wheelbase is the same good call on the power steering box ill look into that i was just looking at the phot of the donor truck and noticed its 5 bolt wheels to my knowledge 71 and 72 only had 5 bolt and switched to disk brakes up front or was this just on the trucks where suburbans different? he said he has owenrship for the body so im assuming the 68 he advertised is correct, ill have to ask him a few more questions before i go down this weekend to look at it.

appreciate the responses guys!

[72chevynut]

Yes suburbans were same as trucks. 71-72 would be 5 lug, front disc brakes. I’m not sure what your looking at, could it be a 71-72 suburban with a 68 front clip? Or maybe 68 with 5 lug conversion. Anything is possible through the past 50 years, lol. I agree, more questions would be good ideal.

[clear-lake-gmc]

Originally Posted by 72chevynut

Yes suburbans were same as trucks. 71-72 would be 5 lug, front disc brakes. I’m not sure what your looking at, could it be a 71-72 suburban with a 68 front clip? Or maybe 68 with 5 lug conversion. Anything is possible through the past 50 years, lol. I agree, more questions would be good ideal.

yes many variables! i just have 1 shot its seeming like it should be a fine swap either way getting excited to get my 71 on the road its my 2nd 67-72 first one never saw the road and this one has been waiting a few years i now have the facilities and knowledge just switched carrers to 310 truck tech so in the right spot and right time to get into the projects!