A shop here in Santa Rosa CA called “The Rear End Shop” has recommended a slightly used GM OEM 3.42 ring and pinion set along with a set of new 28 spline axles if needed. ( I already bought a 28 spline Eaton Posi. and LPW support cover from them.) Ive read some posts and am slightly concerned about the ring and pinions strength. (Car details are in my signature) Its a dally driver that I'm going to take to the strip to get some ¼ mi times but that's it. How do the stock ring and pinion sets compare in strength to the after market sets? And do you think the OEM set is OK for what I'm doing? (May put in a 330 hp GMPP create engine at a later date.) Thanks

 

unless the gears are dirt cheap or free, i would not buy them used.

The ring and pinion are the weak point of the 7.5" axle. They will break sooner or later if you use sticky tires. But people here have managed to get them into the 10's o believe with no breakage, so long as they baby the car off the line.

 

Though it makes no real difference, you'd have a 7.625. The after markets are, of course, stronger--and much more expensive. I'd weigh that cost against a few times down the track. I'm running a 350/330 HO Deluxe with an OE 10-bolt. While I've experienced zero problems, I've also dropped the clutch zero times. I've also retained a non-WC T-5. Conclusion: Wrack and ruin depends on the way you drive.

JamesC

 

OEM gears are usually quieter than aftermarket. If they are set up correctly then they will probably be fine.