I just went to the track last friday, with a rearend i got from a friend with 4.10 gears i got 1 pass and the second it snapped the ring and pinion. I intentionally left 30 lbs in the slicks and launched around 2400 and did not just dump the clutch. Now i know te teeth for a 4.10 gear on a 7.5 ring gear are thin so the question is, how long can a 3.73 gear last? I want to swap the 3.73 in and see what it can do, i have friends with 3.73 gears in a 10 bolt that go 10s but they use a automatic, i use manual trans.

 

Here is the....end of the gear.

 

Much of the strength of a gear set comes from the way that it is set up. If the contact pattern is off then the gear will be weaker than it should be. Pinion depth and backlash are very important. Bearing preload is also important. If the bearings are not preloaded correctly it will allow the parts to move or bind. There is a good chance that the rear end that you bought was not set up right, which may have lead to it's breaking. A 3.73 will be a little stronger and will take a little bit of torque off of the axles.

 

Well, i hope i can score a set and have it set up correctly, i have no idea who set up the 4.10s in this rear. It is a disc brake rear, so i would like to keep it. 3.73 is what i really wanted anyways.

 

Do you have the 26 or 28 spline axles? You might need to upgrade to the larger axles.

 

The rearend is out of a 85 Z28, im not sure.

 

85 woulda been 26 spline, but with 4.10s put in, theres no telling what axles were put in.

 

Well, i assume they are all stock except the gear swap.

 

You can beef up the 10 bolt a little bit but the tiny ring and pinion will always be the weak link.

 

Yea, i think ill try to get my dana 44 back and spend 500$ or so on it to get it right.

 

2-spider will always be a POS.

10-bolt strength=your engine's HP-1