Do I need to break in my rear end?

**toofpaste** · 06-03-2008, 08:25 PM

I just got 2 new rear shafts for my rear end because my old ones were bent and messed up....Do I have to break these shafts in...although I still dont have a "completely" new rear end?

**intheclouds1977** · 06-03-2008, 08:52 PM

New axle shafts do not require a breakin. That's just for new gears.

**clg82** · 06-03-2008, 09:14 PM

Originally Posted by intheclouds1977

New axle shafts do not require a breakin. That's just for new gears.

since we're on the subject of breaking in new gears, i am about to get some installed this weekend, but i have to drive 2 hours away to have it done.....will it hurt the gears to drive straight home?.....what should i do?

**toofpaste** · 06-04-2008, 04:59 AM

Originally Posted by intheclouds1977

New axle shafts do not require a breakin. That's just for new gears.

Thanks, so I'm guessing I can take it to the track as is?

**intheclouds1977** · 06-04-2008, 02:12 PM

Originally Posted by clg82

since we're on the subject of breaking in new gears, i am about to get some installed this weekend, but i have to drive 2 hours away to have it done.....will it hurt the gears to drive straight home?.....what should i do?

That is a terrible idea. Drive for 20 miles and stop for lunch. Then drive another 20 miles and go shopping. Then drive the rest of the way home.

Below is my suggested breakin for gears. If you don't follow this, you're likely to severely overheat your differential, making your new gears much weaker and possibly causing bearing failure.

Fill with fresh gear oil. Drive for 20 miles without hard acceleration and at a steady speed. Do not exceed 60mph. Let the vehicle sit as long as it takes for the differential to become cool to the touch. Repeat procedure one more time.
For the first 100 miles, do not exceed 60mph. After 500 miles, drain/refill with new gear oil. Your new gears are now broken in.