Visit The Dirt Forum for More Information

Author Topic:   stock gm rear ends
racer038
Dirt Maniac

Total posts: 111
posted May 16, 2004 07:25 AM  
Have you all found that stock GM rear ends have a slight toe in built into them? Last year we gave up trying to string the car when we never could get the rear end to string straight. It always came up slightly offset in the car and toed in. This year we're using a new rear end housing, new chassis (mounting points are square) and new rims and the rear still wants to measure a little toed in. It also appears offset to the left about 1 inch. Anyone with a similar experience or knowledge. Our rear ends come out of 77 - 79 GM full size non c-clip type. Thanks!!!

racer038
Dirt Maniac

Total posts: 111
posted May 17, 2004 12:33 PM  
bump

juliaferrell
Dirt Freak

Total posts: 370
posted May 17, 2004 08:33 PM  
bump>? Yes they have some built into them. Remember a truck is made to haul weight!!!

juliaferrell
Dirt Freak

Total posts: 370
posted May 17, 2004 08:39 PM  
Should be able to take you a couple strings and quickly identify the problem. Remember with different offsets and the like you will not just string up square. I always take the string on the drivers side, get a jackstand and wrap string back around tires edge at axle center line, run string across front tire, adjust steering wheel to align string across the good *unbent rim*. When you repeat this on the other side of the car you can immediately see what's going on. If your toe in front is square, you will notice whether the string contacts the front of the rim on the rear. if your track widths are different you have to hold the string out away from the rim that is not as wide. Just a thought on the way I do it. Yes most truck rears have a little camber and about .5 degrees toe built in.

racer038
Dirt Maniac

Total posts: 111
posted May 18, 2004 05:56 AM  
Thanks for the replies. Just to clarify, the rear ends we use are GM full size non c clip, not truck rear ends. The cars are 77 - 79 Olds 98 and Buick 225 with 8.5 ring gears. The axles have a flange that bolts onto the axle housing, holding the axle into the rear end. We use these because they have larger bearings and because we feel they are safer than c clip types. Appreciate all comments and experiences.

fastow
Dirt Maniac

Total posts: 168
posted May 18, 2004 08:16 PM  
I'll throw in two cents worth here ! The way I would check for toe in on the rear is just like the front jack up the rear put a paint mark around a tire in a light colored paint then with a sharp scribe braced on a can or anything sribe a line around the tire one person will need to spin the tire while the other carefully holds the scribe this makes a perfect line around the tire even if you have a bent wheel or anything then let the car down and measure the toe on the rear tires just as you do one the front. I have never thought a little toe really ever hurt you but I think you should know what it is. the right rear toe in will make you a little tighter coming off toe out would make it a little loose. another thing to keep in mind is them housings do torque around when your out there running really hard under acceleration if a tire is really gettin a bite I bet it toes in even further. I have seen where guys have welded brackets for adjustable bracing across the back of the housing useing hiems and swedge tubes you could adjust this some what.
Well maybe I left more than 2 cents worth maybe not but its tax free one way or the other LOL

    

Back to the Archives