How do I identify a GM 12-Bolt?
The easiest way to identify a 12-bolt rearend is obviously by the 12 bolts holding the rear cover onto the axle housing. The pinion shaft on passenger-car differentials is 1-5/8-inch in diameter and the cover is oval, measuring 10-15/16-inches wide by 10-5/8-inches tall.
What did GM 12-Bolt come?
Trucks first started using 12-bolt rearends in the 1965 G-series vans and C-series pickups. They were used until the end of production in 1987. Blazers from 1969 through 1981 also used this differential (four-wheel-drive Blazers had it installed on the rear only).
What size is a GM 12-Bolt?
The GM 8.875-inch, 12-bolt positraction came in many 1965 to ’72 passenger cars. The pinion shaft on passenger cars’ differentials was 1.625 inches in diameter, and the cover was oval, measuring 10.9375 inches wide by 10.625 inches tall.
How do I know what rear end is in my Chevy truck?
All Chevrolet rear ends can be identified by comparing the gasket shape to an identification chart similar to the one found on Drivetrain’s differential identification page (see References). A visual chart of different GM/Chevrolet rear ends is found on Ring & Pinion’s differential types web page (see References).
Are 12 bolt rear ends good?
When the 12-bolt rearend is properly assembled, it’s the strongest passenger-vehicle rearend Chevy ever produced. GM engineers designed the 12-bolt to be a durable piece that could handle the torque output of its big displacement engines.
Whats the difference between a 10 bolt and 12 bolt rear end?
First, the 10-bolt’s pinion shaft diameter is 1.438 (25 splines) while the 12-bolt is 1.625 (30 splines) which makes the 12-bolt 13 percent larger in diameter and therefore stronger. The 8.2 uses a 28-spline axle (1.20 inches in diameter) while the 12-bolt uses a 30-spline axle (1.625 inches in diameter).
What is the difference between a 10 and 12-bolt rear end?
When did GM start using the 12 bolt?
We offer a complete line of rear end parts for the GM 8.875″ commonly referred 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. Having a problem with GM 12 bolt rear end?
What are GM 12 bolt rear end gears made of?
The SVL gear manufacturing process ensures that you get guaranteed performance that is engineered to meet aftermarket demands. The result is Chevy GM 12 Bolt TRUCK rear end ring and pinion gears that deliver performance standards set by DANA, one of the world’s most trusted supplier of driveline parts.
What kind of axle does a 12 bolt Chevy have?
This is the Moser Engineering 12-bolt axle assembly. As you can see, the Chevy 12-bolt differential is one stout axle, and it was the rear axle of choice for GM muscle cars and many GM competition cars.
How can you tell if a truck has 12 bolts?
At a quick glance, you can also tell when you’re looking at a truck 12-bolt, because the rearend cover has an irregular shape. Early truck 12-bolts had axles with 12 large axle splines. The differential carriers are also narrower than those in passenger-car units.