jQuery not supported.



Rear end differential mystery

How do I go about buying a posi diff.

Rear end differential mystery

Postby Killain [OP] » Feb 22 2013, 9:58pm

I'm trying to buy and install a posi-trac differential in my 1990 Chevy 1500 Silverado, it's got a 305 ci. V8 and a 700R4 and the gears back there are 3:42. Can anyone tell me how to go about figuring out if I have a 28 or a 30 spline rear end ? I called a couple of dealers, but they all say the truck is too old to look up any information on. Any ideas are more than welcome. I can buy a brand new Eaton posi-trac for about $450.00 but I need to know what number of splines it has. Thank you !
Attachments
1990 Chevy Pickup 1.20.2013 PICTURES 003.JPG
Original Poster
Killain
Firing on 8 cylinders [L1]
Firing on 8 cylinders [L1]
Posts: 91
Topics: 19
Images: 14
Blogs: 0
Joined: Sep 03 2012, 7:06pm
Years of membership: 1 year of membership
Location: Essington PA
Year: 1990
Make/Model: Chevrolet Silverado
Extra Info: 305 V8
Group Membership:
Registered users
Related Topics  Groan from front end differential?   new rear differential   Rear Differential Positraction   locking rear differential   Rear Differential Gasket   Rear Differential Clatter   2007 4.8 2WD 3.23 rear differential   Changing rear differential oil   Front and Rear Differential Gaskets   Problem After Rear Differential Fluid Change   Rear Differential Capacity & how to see 5/8" from plug?   What rear end to go with?   New rear end????   Rear end gears 
Transmission/Drivetrain Sponsor
Advertise Here

Re: Rear end differential mystery

Postby steved » Feb 22 2013, 10:11pm

Call Randy's Ring and Pinion, they should be able to tell you...
steved
Combustion on 7 pistons [L2]
Combustion on 7 pistons [L2]
Posts: 759
Topics: 37
Blogs: 0
Joined: May 21 2012, 7:45pm
Years of membership: 1 year of membership
Location: Reading, PA
Year: 2012
Make/Model: Chevrolet Silverado
Extra Info: 2500HD 4x4
Group Membership:
Registered users

Re: Rear end differential mystery

Postby Killain [OP] » Feb 25 2013, 10:25pm

How do I contact them ? Thank you !
Original Poster
Killain
Firing on 8 cylinders [L1]
Firing on 8 cylinders [L1]
Posts: 91
Topics: 19
Images: 14
Blogs: 0
Joined: Sep 03 2012, 7:06pm
Years of membership: 1 year of membership
Location: Essington PA
Year: 1990
Make/Model: Chevrolet Silverado
Extra Info: 305 V8
Group Membership:
Registered users

Re: Rear end differential mystery

Postby 19trax95 » Feb 25 2013, 10:32pm

Off topic but....

Thats a pretty clean looking obs you got there.
User avatar
19trax95
Combustion on 7 pistons [L2]
Combustion on 7 pistons [L2]
Posts: 761
Topics: 17
Images: 6
Blogs: 0
Joined: Apr 17 2012, 1:42am
Years of membership: 2 years of membership2 years of membership
Location: eastern PA
Year: 1995
Make/Model: Chevrolet Silverado
Extra Info: 1500 4.3 vortec 4x4
Group Membership:
Registered users

Re: Rear end differential mystery

Postby Killain [OP] » Feb 25 2013, 10:58pm

Whats an OBS ?
Original Poster
Killain
Firing on 8 cylinders [L1]
Firing on 8 cylinders [L1]
Posts: 91
Topics: 19
Images: 14
Blogs: 0
Joined: Sep 03 2012, 7:06pm
Years of membership: 1 year of membership
Location: Essington PA
Year: 1990
Make/Model: Chevrolet Silverado
Extra Info: 305 V8
Group Membership:
Registered users

Re: Rear end differential mystery

Postby 19trax95 » Feb 25 2013, 11:09pm

Obs is just an acronym for old body style. Which encompasses model year 1988-1998. Then there is oobs (old old body style) which is 72-87. Nbs is 99-07.5 and nnbs is 07.5-2013
User avatar
19trax95
Combustion on 7 pistons [L2]
Combustion on 7 pistons [L2]
Posts: 761
Topics: 17
Images: 6
Blogs: 0
Joined: Apr 17 2012, 1:42am
Years of membership: 2 years of membership2 years of membership
Location: eastern PA
Year: 1995
Make/Model: Chevrolet Silverado
Extra Info: 1500 4.3 vortec 4x4
Group Membership:
Registered users

Re: Rear end differential mystery

Postby Daly » Feb 25 2013, 11:18pm

In 1990 they were 30 spline. And +1 on the truck, it is a beautiful looking truck.

I do hate the acronyms for trucks. People should get use to calling them by there GM names, at least from 88 on.
88-98 GMT400
99-07 GMT800
07.5-13 GMT900
What are they going to call the 2014's, NNNBS (new new new body style) It's stupid IMO.
2012 Silverado 4x4, 4.8, Air Raid Jr, 3.5" RC lift (premium kit), 285 Cooper AT3's, 17x9 XD Addicts w/ -12 offset...
Image
Sig thanks to TotalChaos (jeff)
User avatar
Daly
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 4060
Topics: 20
Images: 41
Blogs: 0
Joined: Nov 17 2012, 6:22pm
Years of membership: 1 year of membership
Location: Sarnia, Ontario
Year: 2012
Make/Model: Chevrolet Silverado
Extra Info: Cheyenne Edition
Group Membership:
Registered users

Re: Rear end differential mystery

Postby Killain [OP] » Feb 26 2013, 1:11am

Well then, Thank you very much. I've wanted to install a Posi-trac differential and I have found a few, prices are all about the same $425.00 New, but I didn't know what splines I needed. Thank you. And yes, It is a great looking truck, which took a lot of sweat equity to get to where it is. Thank you for your help !
Original Poster
Killain
Firing on 8 cylinders [L1]
Firing on 8 cylinders [L1]
Posts: 91
Topics: 19
Images: 14
Blogs: 0
Joined: Sep 03 2012, 7:06pm
Years of membership: 1 year of membership
Location: Essington PA
Year: 1990
Make/Model: Chevrolet Silverado
Extra Info: 305 V8
Group Membership:
Registered users

Re: Rear end differential mystery

Postby steved » Feb 26 2013, 3:28am

Randy's Ring and Pinion should have a website. There is also 4xHeaven, which is a little mom and pop type store, but they always treated me well and gave good prices.
steved
Combustion on 7 pistons [L2]
Combustion on 7 pistons [L2]
Posts: 759
Topics: 37
Blogs: 0
Joined: May 21 2012, 7:45pm
Years of membership: 1 year of membership
Location: Reading, PA
Year: 2012
Make/Model: Chevrolet Silverado
Extra Info: 2500HD 4x4
Group Membership:
Registered users

Re: Rear end differential mystery

Postby Killain [OP] » Feb 26 2013, 10:48am

Thank you !
Original Poster
Killain
Firing on 8 cylinders [L1]
Firing on 8 cylinders [L1]
Posts: 91
Topics: 19
Images: 14
Blogs: 0
Joined: Sep 03 2012, 7:06pm
Years of membership: 1 year of membership
Location: Essington PA
Year: 1990
Make/Model: Chevrolet Silverado
Extra Info: 305 V8
Group Membership:
Registered users
Next

Return to Transmission/Drivetrain

 

  • Similar topics
    Replies
    Views
    Last post

Common search terms

rear install mystery differential chevy pretty didn anyone great back welcome help same trucks

It is currently Apr 24 2014, 7:26pm

Login  •  Register
SHOP TALK (Live Chat)
Transmission/Drivetrain Forum
Transmission/DrivetrainTransmission and drivetrain related components. Discuss automatic and manual trans repairs and performance or talk about driveshafts or rear-ends and differentials. Diagnostics of 4-speed, 5-speed, or even 6-speed transmissions.
To create a new topic in Transmission/Drivetrain, click this button:
Previous topic Next topic

Network Link:
Chevy Silverado Parts

Random Image Attachments
Help with Lift
Help with Lift
Attached by: gmctruckguy
Truck vs. ....
Truck vs. ....
Attached by: chrsmddx22
Late Cristmas, early bir...
Late Cristmas, early bir...
Attached by: P-cola-Roy
Lets see 'em
Lets see 'em
Attached by: Jordan_Infranca
Sitewide News Sitemaps & Feeds

Who is online

Users browsing this forum: Netseer [Crawler] and 10 guests