Rear end sitting higher on one side.
Thread Starter
Instructor
Joined: May 2006
Posts: 153
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From: Gautier MS
Rear end sitting higher on one side.
I have noticed, hear of late, that the right side rear end (bumper) of my 90 vette seems to sit a little higher than the left. I followed my dad the other day, who was in my vette, and noticed it. I measured it on level ground an it is about 3/4'' to 1" higher on the right. I have had the complete rear diff swithed out before, due to hitting something in the road and it knocking a chunk out of it. I have also noticed the MPH are about 10 mph slower than I am actually going which is do to a different ratio rear end I'm sure (speedo says 60mph and it's really 70mph). Has anyone had this same problem or know what could have done this? The rear diff was changed about 4 years ago but have just now noticed the difference in bumper height, as I don't follow it very often.
Thanks Matt
Thanks Matt
Melting Slicks
Joined: Aug 2003
Posts: 3,399
Likes: 394
From: Lakeville MI
This is not uncommon.
There are a couple of possible causes.
1. Uneven weight distribution: typically the right rear is about 75 lbs lighter than the left rear, so it will naturally sit higher since a common spring is used. Reducing the preload on the right rear can help to lower that side.
2. The body may not be bonded squarely to the chassis.
3. The rear sway bar may be further preloaded on one side, contributing to the ride height offset.
On my car, I was able to level the rear. I started by moving the battery to the rr storage compartment to help with the weight distribution.
I then adjusted the rear spring pre-load separately on each side with the lowering kit bolts.
The third step (and final breakthrough) was shimming the swaybar mounting bracket on the low side and fine tuning the spring preload side to side.
See my post on this topic:
http://forums.corvetteforum.com/show....php?t=1266609
There are a couple of possible causes.
1. Uneven weight distribution: typically the right rear is about 75 lbs lighter than the left rear, so it will naturally sit higher since a common spring is used. Reducing the preload on the right rear can help to lower that side.
2. The body may not be bonded squarely to the chassis.
3. The rear sway bar may be further preloaded on one side, contributing to the ride height offset.
On my car, I was able to level the rear. I started by moving the battery to the rr storage compartment to help with the weight distribution.
I then adjusted the rear spring pre-load separately on each side with the lowering kit bolts.
The third step (and final breakthrough) was shimming the swaybar mounting bracket on the low side and fine tuning the spring preload side to side.
See my post on this topic:
http://forums.corvetteforum.com/show....php?t=1266609
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
I agree! As far as your speedo it sounds as if you went to a 2.73 gear ratio, which would effect the speedo reading. You can either have it corrected or have a set of 3.07's put back in!
Just the other day there was a set of 3.07's for sale in the Parts/Wanted section of the forum.(I'm going to check it out to see if they are still there) You could also post a thread and someone might have a gear set ready to go!
Thanks, Matt
Just the other day there was a set of 3.07's for sale in the Parts/Wanted section of the forum.(I'm going to check it out to see if they are still there) You could also post a thread and someone might have a gear set ready to go!
Thanks, Matt
Thread Starter
Instructor
Joined: May 2006
Posts: 153
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From: Gautier MS
Thanks tequilaboy, This will give me a good idea of where to start. My brother has a 86 vette and we looked at it the other day and his seems to be level on both sides. We put a carpenter level on the bumper and his was pretty much level and mine showed as I described. As for the rear end I have heard that you can change the speed sensor to correct the mph being off. Will I will need to find out what gears are in the rear and match that to a different speed sensor? Thanks madmatt, but not interested in changing gears at this time.
