12 Bolt Chevrolet GM 8.875

Chevrolet GM 8.875" 12 Bolt Truck Ring and Pinion Sets

Having a problem with GM 12 bolt rear end? We offer a complete line of rear end parts for the GM 8.875" commonly refered to as the 12 Bolt truck differential, this differential was utalized GM used this very popular differential in there full size Chevrolet trucks starting in 1964 to 1982. Our inventory includes ring gear and pinion sets, including aftermarket and OE gear sets. We are able to supply axles, bearing overhaul kits, carriers, cases, spider and side gears.

The Positraction units we offer include Lockright, no-Slip Powertrax, Auburn, Eaton Posi, Detroit Lockers and TrueTrac . We are a Dana Spice volume distributor and offer a complete line or ring gear and pinions to the large Dana 80 differential. In addition to the Dana Spicer line we quality offer differential products.

Specifications are provided below to assist you in the identification and setup as well as torque spec's for your Chevy or GM 8.875" differential.

GM 8.875" 12 Bolt Applications 1/2 & 3/4 ton trucks
Model	Year
G20, G25	64-82
G10, G15	64-81
K10, K15, C10, C15	64-82

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Need information on how to setup ring and pinion backlash

Purchase your parts @ drivetrain.com and receive telephone access to experienced differential technician to assist you with installation, we help you solve the problem.

Specifications

11-1/2"
12 HOLES
Irregular Gasket Pattern

RG Diameter 8.875"
12 3/8" X 24 RH Threaded Bolts
PINION Diameter 1.438", 30 Spline
CASE: 2.56 -2.73, 2.76-3.42 & 3.73 Numerically Higher

8620 Material Heat-Treated

Assembly Specifications:
Cover Bolt Ft. Lbs. 20
Pinion Brg. Preload In. Lbs 24-25
Pinion Brg. Preload In. Lbs 10-15 Used
Ring Gear Backlash .005-.009
Ring Gear Bolt to case Ft. Lbs. 90
Side Brg. Caps Ft. Lbs. 60

GM 8.875" 12 Bolt Differential Ring Gear and Pinion Set			Quaility Gears provide guaranteed performance		Order above high performance synthetic oil and friction additive combo kit at time of order for ring and pinion or bearing overhaul kit and pay only $49.95 plus S&H, a $54.00 value. See other Red Line Oil Products that we recommend.
Part Number	OE Number	Ratio	Teeth	Price
GM12-308		3.08	40-13	$214.94
GM12-342		3.42	41-12	$214.94
GM12-373		3.73	41-11	$214.94
GM12-373X*		3.73	41-11	$214.94
GM12-411		4.11	39-9	$214.94
GM12-411X*		4.11	37-9	$214.94
GM12-456		4.56	41-9	$214.94
*Fits 2.76 go 3.42 Case

GM 8.875" 12 Bolt Differential Parts
Description	Part Number	Price
Case, Empty Open 8.875" 3.73 -UP	6258086	$319.99
Case, Empty Open 8.875" 3.42 -Down	6258088	$395.00
Bearing/Overhaul Kit 8.875" Rear	DTSR12RMK	$102.82
Internal Kit 8.875" 30 spline Open (spider/side gears, cross shaft thrust washer)	GM12BI	$116.26
Axle 30 Spline, 65-69 30 3/4" long 6 holes R&L	PA6068	$142.52	Installation Tool, Your Cost $49.98 + S&H
Axle 30 Spline, 65-69, 6 hole to 5 hole conversion L&R. 30 3/4" length.	PA5855	$188.78
Axle 30 Spline 4wd 70-81 31 9/32" length 6 hole	PA5383	$136.86
Axle 30 Spline 2wd 70-81 31 5/16" length 5 hole	PA5569	$136.86

GM 8.875" 12 Bolt Differential Positraction Units			Whats the difference in Positractions? Differentials whats the Difference
Description	Part Number	Price
Auburn Limited Slip Positraction 30 Spline	542032	$571.95
Auburn Limited Slip Positraction 30 Spline	542034	$ 571.95
Detroit Locker 30 Spline	187C150A	$808.19
Eaton Large Hub GM GM Truck 1961-1980, 30 spline, 3.42 & down	19587-010	$485.48	Recommended replacement for non-repairable non-working GM stock Gov-loc positraciton
Eaton Large Hub GM Truck 1961, to 1980 30 spline, 3.73 & up	19556-10	$485.48
TrueTrack 30 splines	913A315	$573.63
LockRight 1/2 Ton Pickup 30 Spline	1910	$297.72
no-Slip Powertrax 30 spline	92-0788-3005	$452.76

GM 8.875" 12 Bolt Applications 1/2 & 3/4 ton trucks

GM 8.875" 12 Bolt Differential Ring Gear and Pinion Set

GM 8.875" 12 Bolt Differential Parts

GM 8.875" 12 Bolt Differential Positraction Units