Need help! Two Questions on a 9.25 true lock diff 3.90 ratio
 

Hx: 2003 Dodge Ram 1500 5.7L 167,000 miles 9.25in 3.90 ratio Stock rear end Pinion bearing blew out and destroyed everything including the carrier. So Im looking for some advice.

First question is, Does anyone know any effects on changing from the 3.92 stock ring (47 teeth) and pinion (12 teeth) to another 3.9 ring (39teeth) and pinion (10 teeth), such as milage,etc?

I understand it the same ratio but I just want to make sure I'm not forgetting anything before I pull the trigger on this.

Second Question is, Can anyone recommend a Limited Slip diff carrier that works well with the exciter ring on these dodge rear ends?

I use the truck as my daily short trip ,to highway miles once a month and off road during deer season.

PS: Parts Geeks has bad (NO) costumer service and will never use them again!

Post a link where you found a 3.90 gear set at please.

Auburn LSDs work great. I have on in mine

3.90? where did you find?klow tooth count sounds like its for a smaller rear end, like 8.5".
Also never heard of 3.90? Only 3:92 (47/12 = 3.9166667) So, if you have 4wd, you WILL have a problem if not matched exactly.

Lastly, where are you located? Limited slip is good, but a Detroit Trutrac is better for bad weather driving than the auburn. A bit pricer but worth it. If your in warmer climate, get the Auburn and save your money.

Here is the link
 

http://www.partsgeek.com/catalog/200...nd_pinion.html

Not sure what to do now, After having all the problems with Parts Geeks already this just makes me more upset. Can 0.0166666 difference in ratio from front to rear really cause damage. If yes, I get why but Im just pissed Parts Geeks sold me something that is not exactly what I asked for.

Im located in Austin Texas and we do get foul weather sometimes. I have had pour handling in rain and on ice. Actually ended up in a ditch 2 different times , once while avoiding a on coming car that came into my lane while it was pouring rain and another I hit ice on a bridge and managed to hold it together.

Gear ratio difference % from front to rear
 

I was under the impression that it might not be perfect but would not cause damage if gear ratio difference from front to rear was less than 1%. Have even heard of 2%! but with just around 1/2 of a percent difference do I really need to stress it?

Maybe I'm doing the math wrong! I thought 3.92/3.90=1.0051282 or 1/2% difference........and if i do it exact 3.9166667/3.90=1.0042735 or even less than 1/2% difference

As long as it is a matching set made for the Chrysler 9.25 rear, the ratio is irrelevant. Your speedo will be a bit off but that can be fixed with tuner

do you have a part # and place where you got your Auburn Diff carrier?

Not off hand. Google it or got to Auburngear.com

Auburn Limited Slip 9.25! Package deal, everything you need to DIY! Everything BNIB!

Take the space out from Dodge and Talk to me the link complete

http://www.dodge talk.com/forums/showthread.php?t=508457