Lift questions???? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

kevinr1970 · 01-11-2007, 01:55 PM

Might be better in the suspension section but I'll start here.

I swapped the 2” lift springs from my parts truck (’85 GMC ½ ton swb) to my good truck (’86 GMC ½ ton lwb).

Before I started the swap, when the trucks were parked grill to grill, the hood and bumper of the ’85 parts truck was noticeably higher than the ’86 good truck.
The ’86 had 33x9.5 and the ’85PT had 33x10.5 tires. When off the trucks the tires looked to be almost exactly the same height.
On the ’85PT I measured the distance from the center of the front hub to the edge of the fender (straight up) at 23-1/2”. The distance on the rear was 24-1/2”. On the ’86 it measured 21-3/4 to 22” (little different side to side) and 22-1/2”.

My problem is now that the lift is on my ’86 the ’85PT still sits slightly higher than the ’86? The kicker is that the ’86 is sitting on the 33x10.5’s but the ’85PT is sitting on 31x10.5’s????

The rear of the ’85PT is on jack stands so it will come up some when I mount the axle and set it on tires. It should bring the front down a little bit. I wouldn’t think it would come down more than just about level with the ’86 though. But with a 1” drop because of tire size and a 2” drop in springs the ’85PT should be 3” lower than the ’86.
When I measure the ’85PT it is now about 23-1/4”. The ’86 is about the same. The rear of the ’86 is noticeably higher but it looks like it is jacked up in the back – it slopes down to the front.
I measured the shackles (? the rear mounting brackets for the front springs) at I think 4-1/2” from bolt hole to bolt hole. It was the same on the ’85 parts truck.

WHAT AM I MISSING HERE??????

Prerunner1982 · 01-11-2007, 02:48 PM

Does the parts truck have an engine in it? The lack of that extra weight makes the front sit quite a bit higher.

kevinr1970 · 01-11-2007, 03:35 PM

Yes, its a runner and (was) a driver. Both small blocks.

Billy81 · 01-13-2007, 07:55 PM

Does the PT have a body lift on it?

kevinr1970 · 01-14-2007, 02:28 AM

Nope, no body lift.
I've come to the conclusion that the front springs from the parts truck are shot. I was thinking that I was going to take the springs I removed and reinstall them but with the helper spring that came from the PT.
But I might just wait for the tax refund and buy some new 2" front springs.

f.monroe · 01-14-2007, 10:24 PM

Are the jack stands under the axle or on the frame because I know that would make a difference . ? Frank

01-11-2007, 01:55 PM	#1
kevinr1970 Senior Member Join Date: Aug 2004 Location: Everett, WA Posts: 2,316	Lift questions???? Might be better in the suspension section but I'll start here. I swapped the 2” lift springs from my parts truck (’85 GMC ½ ton swb) to my good truck (’86 GMC ½ ton lwb). Before I started the swap, when the trucks were parked grill to grill, the hood and bumper of the ’85 parts truck was noticeably higher than the ’86 good truck. The ’86 had 33x9.5 and the ’85PT had 33x10.5 tires. When off the trucks the tires looked to be almost exactly the same height. On the ’85PT I measured the distance from the center of the front hub to the edge of the fender (straight up) at 23-1/2”. The distance on the rear was 24-1/2”. On the ’86 it measured 21-3/4 to 22” (little different side to side) and 22-1/2”. My problem is now that the lift is on my ’86 the ’85PT still sits slightly higher than the ’86? The kicker is that the ’86 is sitting on the 33x10.5’s but the ’85PT is sitting on 31x10.5’s???? The rear of the ’85PT is on jack stands so it will come up some when I mount the axle and set it on tires. It should bring the front down a little bit. I wouldn’t think it would come down more than just about level with the ’86 though. But with a 1” drop because of tire size and a 2” drop in springs the ’85PT should be 3” lower than the ’86. When I measure the ’85PT it is now about 23-1/4”. The ’86 is about the same. The rear of the ’86 is noticeably higher but it looks like it is jacked up in the back – it slopes down to the front. I measured the shackles (? the rear mounting brackets for the front springs) at I think 4-1/2” from bolt hole to bolt hole. It was the same on the ’85 parts truck. WHAT AM I MISSING HERE?????? __________________ 2009 Honda Fit CfC (bsf 44.9 mpg) 2000 Tahoe Limited 1991 GMC CrewCab Dually 2wd, will end up swb, not dually and replace CCswb below 1991 GMC CrewCab Dually 4x4, just going to fix things up for now 1982/1989 K5/GMC Jimmy 2wd 1987 GMC 1/2 ton swb 2wd Crew (sold)

01-11-2007, 02:48 PM	#2
Prerunner1982 Registered User Join Date: Oct 2002 Location: Edmond, OK Posts: 5,904	Re: Lift questions???? Does the parts truck have an engine in it? The lack of that extra weight makes the front sit quite a bit higher. __________________ Jon 1982 Chevy Silverado 350/th350.... RETIRED 1993 Jeep XJ 2 door(Cherokee) 4wd 4.0ltr/AX-15 (5spd)/NP231 .... Oklahoma Roll Call

01-11-2007, 03:35 PM	#3
kevinr1970 Senior Member Join Date: Aug 2004 Location: Everett, WA Posts: 2,316	Re: Lift questions???? Yes, its a runner and (was) a driver. Both small blocks. __________________ 2009 Honda Fit CfC (bsf 44.9 mpg) 2000 Tahoe Limited 1991 GMC CrewCab Dually 2wd, will end up swb, not dually and replace CCswb below 1991 GMC CrewCab Dually 4x4, just going to fix things up for now 1982/1989 K5/GMC Jimmy 2wd 1987 GMC 1/2 ton swb 2wd Crew (sold)

01-13-2007, 07:55 PM	#4
Billy81 Registered User Join Date: Jun 2004 Location: Medford,Oregon Posts: 390	Re: Lift questions???? Does the PT have a body lift on it?

01-14-2007, 02:28 AM	#5
kevinr1970 Senior Member Join Date: Aug 2004 Location: Everett, WA Posts: 2,316	Re: Lift questions???? Nope, no body lift. I've come to the conclusion that the front springs from the parts truck are shot. I was thinking that I was going to take the springs I removed and reinstall them but with the helper spring that came from the PT. But I might just wait for the tax refund and buy some new 2" front springs. __________________ 2009 Honda Fit CfC (bsf 44.9 mpg) 2000 Tahoe Limited 1991 GMC CrewCab Dually 2wd, will end up swb, not dually and replace CCswb below 1991 GMC CrewCab Dually 4x4, just going to fix things up for now 1982/1989 K5/GMC Jimmy 2wd 1987 GMC 1/2 ton swb 2wd Crew (sold)

01-14-2007, 10:24 PM	#6
f.monroe Senior Member Join Date: May 2004 Location: Caldwell,Tx. Posts: 3,648	Re: Lift questions???? Are the jack stands under the axle or on the frame because I know that would make a difference . ? Frank __________________ Born and proudly residing in a Red State !



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