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| | | | Joined: Nov 2005 Posts: 123 Shop Shark | | Shop Shark Joined: Nov 2005 Posts: 123 | 1950 3/4 ton i swapped the rear end and put in one from an 81 firebird. Before i get spring perches welded what should i set the pinion angle to? How do i measure it? How far up can i tilt the rearend? The body is off does that make an difference? I am worried about tiltting the rearend too much,will it still work right? As you can see this is a first for me. | | | | | Joined: Oct 2009 Posts: 37 New Guy | | New Guy Joined: Oct 2009 Posts: 37 | I assume you are using a jump joint to go from the 3600's drive shaft to the firebird's axle? Thats a huge difference and you will want to align these closely.. sure you want that car axle in a 3/4 ton?
With the box not being on the truck you will want to make sure you have the axle closely centered from side to side.. else you get a tire rub on floor supports
good luck | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | At the top right of this very page there is a tab for "Tech Tips" In there you'll find this very handy Tip for setting up drivelines. http://www.stovebolt.com/techtips/driveline/setup/index.htmlSome short answers: You want to do this with the complete truck, loaded as you'll likely drive it, bed on for sure. The pinion shaft should be parallel to the transmission output shaft. Read the manuals, it's some cool stuff and I bet you have fun with this little project. Grigg | | | | | Joined: Nov 2005 Posts: 123 Shop Shark | | Shop Shark Joined: Nov 2005 Posts: 123 | not sure what you mean by a jump box???
why not use a firebird axle??? | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | not sure what you mean by a jump box??? I assume you are using a jump joint to go from the 3600's drive shaft to the firebird's axle? A conversion U-joint, one that fits the 1350 series Joint on the 3/4 ton driveshaft and the likely smaller size on the new pinion yoke. Why not use a firebird axle? Depends on how you want to use it, it's probably not rated to hold the weight the 3/4 ton truck axle was. Grigg | | | | | Joined: Jun 2009 Posts: 1,596 'Bolter | | 'Bolter Joined: Jun 2009 Posts: 1,596 | As was said already, you can't weld your perches on the axle until you have the entire truck put together the way you'll drive it. Then you can set your pinion angle and make sure it's centered properly. | | | | | Joined: Apr 2001 Posts: 268 Shop Shark | | Shop Shark Joined: Apr 2001 Posts: 268 | Plane or angle needs to be the same as the center line of the crank shaft and transmission output shaft. If the crankshaft, trans output shaft has a 10 degree angle then the pinion shaft has to have an identical 10 degree angle.
Also the frame-line center-lime (side to side)has to also be the same. No offset of center line.
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1948 GMC FC101 1/2t Pickup w/270 and SM420
1948 GMC FC253 1t Factory 80"x9' Flatbed Dually
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1950 GMC 354-24 2 Ton 8'X12' Flatbed w/Dump Hoist
1953 GMC 454-30 3 Ton 8'x14' Flatbed w/Dump Hoist
1953 GMC 454-30 3 Ton Cab and Chassis
1942 Clarkator 6 MILL-44 Heavy Aircraft Tug
1942 Ford (9N) Moto Tug with 1/2 yard Loader
1947 Oliver OC3 HG-42 Tract-Crawler Bull Dozier w/6' Blade
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | ..Also the frame-line center-lime (side to side)has to also be the same. No offset of center line. Offset centerline side to side is OK so long as they are also parallel in that plane. Only complication is you need to do the trig to find the total angle and check that is under the maximum recommended angle for the U-joint. It's all in those Spicer manuals.. http://www.stovebolt.com/techtips/driveline/setup/index.htmlGrigg | | |
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