need rear end help on 87 Grand Prix - Hot Rod Forum : Hotrodders Bulletin Board -- Hot Rod Forum

Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 10-18-2003, 01:20 PM
Registered User
Join Date: Oct 2003
Posts: 12
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
need rear end help on 87 Grand Prix

I have an 87 Grand prix that I will be putting in a 350 in the next few months. I will use the existing 200R4 tranny. I have an 86 Caprice as a engine doaner since it had a new GM 350 installed about 70000 miles ago, but it was wreaked, and saw that it had a 8.5" 10 bolt rear with 3.08 gears. I need to swap gears anyway in the GP and was going to use that, but the housing is a little wider and the shock mounts and all are not the same.

What rear can I use that will be a direct bolt in that would already have 3.x gears in it? Posi preferred. Id like it to be stronger than the 7.5" rear I have now. Any ideas??

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 10-18-2003, 06:19 PM
DoubleVision's Avatar
Not Considered a Senior Member
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 43
Posts: 10,733
Wiki Edits: 0

Thanks: 19
Thanked 77 Times in 71 Posts
likely the cheapest way would be to find a rear out of a 82-87 firebird t/a or camaro Z28. this is also a 7.5 and they had optional posi`s installed, just swap the guts to your rear, it`s what I did in my cutlass and I`m running a warmed over 350 and the 7.5 holds up well as long as slicks aren`t used. the code on the F body rear`s will be on the front passenger side tubes, these are posi rear codes as follows:

Year Code Ratio
1982 2JR 3.42:1
1982 2JY 3.08:1
1982 2JZ 3.23:1
1982 2PZ 3.23:1
1982 2PY 3.08:1
1983 4JQ/5JQ 3.73:1
1983 4JR/5JR 3.42:1
1983 4JY/5JY 3.08:1
1983 4JZ/5JZ 3.23:1
1983 4PQ/5PQ 3.73:1
1983 4PY/5PY 3.08:1
1983 4PZ/5PZ 3.23:1
1984 6EF 3.42:1
1984 6EP 3.42:1
1984 6JQ 3.73:1
1984 6JR 3.42:1
1984 6JY 3.08:1
1984 6JZ 3.23:1
1984 6PQ 3.73:1
1984 6PY 3.08:1
1984 6PZ 3.23:1
1985 8JP 3.08:1
1985 8JQ 3.23:1
1985 8PP 3.08:1
1985 8PQ 3.23:1
1985 8PR 3.42:1
1985 8PS 3.73:1
1986 2H5 3.73:1
1986 2HT 2.73:1
1986 2HV 2.73:1
1986 2HY 3.23:1
1987 2HQ 3.23:1
1987 4HF 3.08:1
1987 4HY 3.23:1
If you use one, make sure you use GM limited slip differential additive, it`ll be in a small plastic bottle from any GM parts counter for around $10, it`s the only thing I`ve found thus far that keeps them from chattering.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-18-2003, 08:23 PM
Registered User
Join Date: Oct 2003
Posts: 12
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I was kind hopeing that there would be a rear already set up that would just swap. Id rather not have to swap the guts. Im assuming that swapping the guts requires reshimming the lash and using the paste to see the proper pattern. Ive never done that and would rather not have to as of yet. I do have some used parts connections and some parts I can barter with, so the cash is not that much of an issue. Im looking for more of a simple stick the rear under the car, bolt in down and drive off kind of thing. Is that possible, or is the Grand Prix setup with shock mounts behind the tubes a one of a kind thing?
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -6. The time now is 01:22 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.