Ring & pinion issues
 

I'm looking for suggestions or comments.. Thanks..
The story: Purchased a 67 3/4 ton, th400, Eaton rear, 32" commercial truck tireson 16 " rims, Drum brakes- 8 lug,,,
Truck was carrying an Alaskan POPup camper ( approx 1600lbs ). i had wanted to ditch the tall tires to rid myself of the tire 'wine' on the freeway.....

I sold the camper to pay for a disc brake/ power booster set up, Then added drop spindles & coils. Found a great set 8 lug- 17" Weld Conehead wheels, added a set of Continental radials- only the tires are 28" tall.

Question - did GM offer other diff. that were 8-lug but w' taller gearing, I must have 4:10 gears.
any help or suggestions please..
Thanks, jim
YIKEs ,, -Sorry I mis typed, I was so rattled on my new dilemma -thanks for the 'heads up-'IvanD..

Re: Rack & pinion issues
 

Are you in the right subforum here? Nice lookin truck btw!

Re: Rack & pinion issues
 

Sorry, I hoped there were some 3/4 drivers here. Not sure if the 73-83 came with spring or coils....and if there were any similar issues..
thanks Rc415
jim

Re: Rack & pinion issues
 

On the back they have leaf spring, and up front they have springs, for 2wd anyway. Thats about all I know.

Re: Rack & pinion issues
 

fourty1 welcome to the 73-87 forum. This generation of trucks came with 4.10, 3.90, 3.73, 3.42, 3.08 and higher. The problem with looking at a 73-87 rear end might be the width. I know some of the 67 to 69(?) had a different width rear axle. You need to verify the width of your axle before considering a later generation conversion.

BTW- I saw what a steal you got on your wheels. I need to take you with me when I shop. The truck turned out awesome....:)

Re: Rack & pinion issues
 

Jim, yer thread should be titled "ring and pinion issues" as rack and pinion is something completely different and refers to steering systems. Anyhow, on yer question - you only need to swap the gears in yer rear end, no need to swap the complete differential or the whole rear axle. I believe the 8-lug 3/4 axles are the so-called "14-bolt semi-floater", which use 9.5" ring gear and have left the factory with 4.11 gear ratios. You might also have the 8.875" ring gear (12-bolt axle), tho I kinda doubt it, but even if you do have that there are 4.11 gears for it too. Really, look up yer build sheet (should be in the glove box), find the RPO code for the axle, and look it up here - there are also pictures and info on different GM axles on this website, which will help you identify what you have, so use them and report back with yer findings.