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| | | | Joined: Dec 2008 Posts: 59 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 59 | Whats the proper way to measure a rear diff for fit? Is it backing plate to backing plate or from the outside edges of the brake shoes?
"One thing about trains, it doesn't matter where the're going, what matters is, deciding to get on." - Polar Express
| | | | | Joined: Jan 2012 Posts: 162 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2012 Posts: 162 | I always measure mine from the outside of the axle flange or from the outside of the brake drum, depending on whether it is disc or drum. Final measurement is going to depend on what wheel and backspacing combo you decide to use, so you have a little bit of leeway but not a lot!
Mitch | | | | | Joined: Dec 2001 Posts: 14,522 Moderator: Welcome Centre, Southern Bolters, Legion Hall | | Moderator: Welcome Centre, Southern Bolters, Legion Hall Joined: Dec 2001 Posts: 14,522 | ...some places I have visited list the space from backing plate to backing plate while others list it as mounting surface to mounting surface (outside of axle to outside of axle) so just make sure you read things correctly when you are checking around. | | | | | Joined: Feb 2001 Posts: 1,094 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,094 | Measure the old one, backing plate to backing plate. Measure from axle flange/brake drum to axle flange/ brake drum. Most cases it can't be bigger in overall length than the original was, or you will have tire fitment issues.
Tommy
59 apache 1/2t
261 short stepside
| | | | | Joined: Apr 2005 Posts: 177 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 177 | the best way is to get the tires and wheels that you want to use and put them in the fenders then measure from the mounting surface of the rims to see how wide it needs to be .i always measure from wheel mounting surface to wheel mounting surface . rear ends do not have the same size brake drums or rotors +the offset of the wheels make a difference | | |
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