Quick Answer

Your Question How many splines does a 12 bolt have?

In stock form, a 12-bolt is equipped with a 30-spline axle. In comparative shear strength, a 35-spline axle (using the MW spline as an example) is 89% stronger.

Are all 12 bolt rear ends the same?

A different 12-bolt differential was used for light truck applications, but those 12-bolt units are not directly interchangeable. You can identify a truck differential by the smaller, 1.438-inch diameter pinion shaft and the size of the rear cover, measuring 10.875 inches by 10.875 inches.

Are 10 bolt and 12 bolt axles the same?

12 bolt axles have 30 splines, 10 bolt have 28, but yet both axles are the same lenth and diameter. That means that if the 10 bolt had a 30 spline carrier the 12 bolt axles would bolt in.

How do you measure the axle on a GM 12 Bolt?

This is simply the make and model of the rear end you are working on. Examples of this is GM 12 Bolt, Mopar 9 1/4, Ford 8.8, etc… This should be measured with a tape measure by hooking the outside of the axle flange (wheel side-where the wheel studs are) and pulling back to the end of the C-Clip Button.

How many splines does a 12-bolt rear end have?

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. But it’s rare to see pinion shafts twist. The weak point is actually out at the axle splines.

How do I know if I have a Ford 9 inch rear end?

Many enthusiasts will tell you to look for the two dimples in the rear cover to determine if the unit is a 9-inch, but this is not always true. Ford also had an 8-inch third-member rear end that had a dimpled cover. The best test of a 9-inch carrier is to try removing the two lower carrier case bolts.

Why is a 12 bolt rear end good?

The 12-bolt positions the pinion-gear higher on the ring gear, which reduces the load on the pinion. This results in less parasitic loss from the friction caused as the gears mesh. Introduced in 1964, the 12-bolt rearend became a staple for Chevrolet racers.

Is a 12 bolt rear end strong?

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.

How can you tell a 12 bolt posi?

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.

How much horsepower can a 8.2 10-bolt handle?

Roughly 550 to 600 HP total. No slicks, drag radials. No problems with the 8.2 at all. I used the stock diff., the Auburn would be better.

What is a GM 10-bolt?

The GM 10-Bolt semi-floating rear axle has been in use for over 40 years. It’s been used in passenger cars, and light duty pickups and SUVs over the decades.

How strong is a Chevy 10-bolt rear end?

The smaller 7.5- and 8.2-inch 10-bolt rear axles can’t transmit horsepower loads in excess of 400 hp. However, the 8.5- and 8.6-inch 10-bolts are extremely stout and effective rear differentials that can transmit up to 1,000 hp to the rear wheels.

How do I know what axle shaft I have?

How to Identify Your Differential &amp
Axle Type | Differential Tech Tips

Where is the axle shaft measured?

How to Measure a Semi-float Rear Axle Shaft | Differential Tech Tips

How do you measure for a new axle?

With the wheels in position, measure from the mounting surface of the drivers side wheel to the mounting surface of the passenger side wheel. This will give you the proper wheel to wheel measurement. Now, subtract the thickness of any disc brake hats or drums and you will have the axle flange-to-flange dimension.

What gear ratio is a 12 bolt rear end?

A wide variety of aftermarket gear ratios are available and Strange carries many GM 12 Bolt 8.875 gears in stock.

What is the strongest rear end?

Dana 60 Rear End Assemblies

If you want a big brute of a rear end under your car, look no further than a Dana 60. Even in the heyday of muscle cars, Dana 60 rear differentials were renowned for their strength, along with their difficulty to locate.

How do I know what GM rear end I have?

Identify your GMC or Chevrolet rear end gear ratio by the RPO Codes, usually located on the placard labeled “Service Parts Identification” inside the drivers door panel or glove box.

Why is it called a 9-inch rear end?

The Ford 9-inch rear end, so named because of its 9-inch ring gear diameter, was manufactured from 1957 to 1987 by the Ford Motor Company and installed in some intermediate and most full-size Ford, Lincoln, and Mercury passenger cars, F-Series ½-ton trucks, and Econoline vans.

What did the Ford 8.8 come in?

First appearing in 1977, the 8.8 is found in almost all Ford V8 cars from ’86 on, and in V6 Rangers and Explorers. There are 24 different Fords that offered the 8.8 rear axle. The weakest points of the 8.8 are the 28-spline axles (1.18 inches in diameter).

What is special about a Ford 9-inch rear end?

The 9-inch Ford Rearend is the Strongest Rearend Out There—It’s All Due to “Hypoid Distance” 1] The 9-inch Ford has no differential case gear-ratio range restrictions
one differential accepts all gear ratios from the 2s through the 6s.

Did Pontiac make a 12 bolt rear end?

Although Buick, Pontiac and pre-’67 Oldsmobiles used the same basic 8.2-inch 10-bolt differential (1967-’70 Oldsmobiles used the Olds-specific 12-bolt 8.5-inch differential), these are different from the Chevrolet 8.2 10-bolt offerings.

What is the difference between a car and truck 12 bolt rear end?

They are two different rear ends, and the car is better in nearly every way. If I am not mistaken the 8.5 10 bolt is stronger in more ways too then the truck 12 bolt. The only things that make’s the 8.5″ &amp
the Car 12-bolt stronger is the larger pinion stem diameter &amp
only seen one break.

How many quarts is a 12 gauge bolt?

Registered. A 12 bolt should only take around 3 quarts until it comes out the fill hole.

What size is a GM 12 bolt rear end?

GM 12 Bolt Specs

Applications: 1964 – 1982 Chevrolet & GMC 1/2 ton to 3/4 ton trucks
Ring Gear: 8.875″
Axle Spline Count: 30 spline
Axle Tube Diameter: 3.00″
Pinion Diameter: 1.625″

How do I know if my Chevy posi is rear end?

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 &amp
Pinion’s differential types web page (see References).

What rear end came in a 57 Chevy?

Automatic 57 cars (both 6 and V8) came with 14inch tires and 3:36 rear gears. Stick shift 57 cars came with 14 inch tires and 3:55 gears.