8.5 0r 8.2 posi - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- 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
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 05-24-2004, 02:48 PM
interceptor429's Avatar
New Member
 
Join Date: Dec 2003
Location: ft.knox ,ky
Age: 51
Posts: 19
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
8.5 0r 8.2 posi

could someone tell me how to tell the difference between the 8.5 and the 8.2 the posi unit is out of the differential and the guy doesnt know which it came from ,any help on how to i.d. it would be great,thanks interceptor,keith

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-24-2004, 07:21 PM
M&M CUSTOM's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Transmission identification
Last journal entry: 1988 Suburban, the project continues.
Last photo:
Join Date: Mar 2003
Location: Northwest Pennsylvania.
Age: 42
Posts: 2,230
Wiki Edits: 9

Thanks: 0
Thanked 1 Time in 1 Post
Are there any casting numbers on it?

Is the ring gear still bolted to it?

Both have a ring gear to carrier bolt count of 10.

Are the splines in the carrier able to be seen, if so then-

The 8.5 would have a spline count of 28, and the 8.2 would have 25.

The 8.2 above would be a 64-72 "Chevy" and the 8.5 would be a early 70's in the range of 70/71/72 or later.

Is the pinion gear available?

And last but certainly not least is the axle housing still able to be found?
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-25-2004, 01:23 AM
Member
 
Last photo:
Join Date: May 2003
Location: Shreveport LA
Age: 64
Posts: 5,103
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The Chevy 8.5" 28-spline posi carrier comes in 2 versions. The 2-series, used with 2.56 & lower ratios, has a casting number ending in -409. The 3-series, used with ratios from 2.73 up, has a casting number ending in -408.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 05-25-2004, 04:34 PM
Ghetto Jet's Avatar
current hot rod: CTS-V
 

Last journal entry: Lets Get Started With the Improvements
Last photo:
Join Date: Nov 2003
Location: Pennsylvania
Age: 28
Posts: 1,726
Wiki Edits: 0

Thanks: 10
Thanked 5 Times in 5 Posts
the 8.5's have strong 1.625" diameter pinions with 30 splines (like the GM 12bolts), while the 8.2 (chevy not the 8.2 BOP used) only have 1.438" pinions with 25 splines.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 05-27-2004, 01:30 PM
Member
 
Last photo:
Join Date: May 2003
Location: Shreveport LA
Age: 64
Posts: 5,103
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I just saw on another board that the 8.5's have 7/16" ring gear bolts, while 8.2's have 3/8".
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply
Message:
Options

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:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

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 04:02 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.