Changing Rear Gears, Anybody tackle them themselves?

[uvraise]

Just curious if anyone has done this themselves? If so, what kind of job was it? Would you do it again or have it done professionally? Thanks for the input!

[URDAMAN]

Install for mine went well, i didnt need any shims perfect fit with oem 1le 3.91s Recommend buying the lucas gearoil with friction modifier. Also a dial indicator to set up the back lash.

[URDAMAN]

Oh... before you crack her open, think about a posi mod or truetrack

[Skipp65]

Where did you get your gears from?

[URDAMAN]

http://www.gmperformancemotor.com/parts/19301504.html

[Bandit63]

Originally Posted by URDAMAN

Oh... before you crack her open, think about a posi mod or truetrack

Which one did you go with?

[URDAMAN]

Started with JRE billet caps because of my budget at the time, I had a whine and it "felt" to tight for me so I switched and love it. http://www.drivetrainspecialists.com...t-912a686.html

[Gunmetal Speedster]

Originally Posted by URDAMAN

Started with JRE billet caps because of my budget at the time, I had a whine and it "felt" to tight for me so I switched and love it. http://www.drivetrainspecialists.com...t-912a686.html

Pardon my ignorance for I am uneducated when it comes to this. But I was considering 4.10 gears for my car, if I bought what you just linked, would I be able to install the 4.10's in that and then just swap out the entire thing with what is on my car? Or am I looking at this wrong?

[paul84043]

The trutrac replaces your LSD, so yes, you would bolt up your gearset to the Trutrac, replace your pinion and that will replace all of the "Guts" of your diff.

Word of warning, the TruTrac can literally be "clunky" in a standard transmission vehicle and there's little you can do about it, it's just the nature of the beast due to the fact that the LSD takes about 1/4 turn of the driveshaft to spool and unspool..
I've been running an Eaton Trutrac in my Jeep for 4 years and have for the most part perfected shifting without the clunk but if anyone else drives it....it's rough. It's clunky but bulletproof.

I would have this done by a shop unless you're an experienced mechanic.

[URDAMAN]

What Paul states is true. But for me; its purpose built and for track results. You will have to relearn the "feel" of your car. No it doesnt ride like stock, but man the performance well worth it...jmo

[OHIOSS]

Originally Posted by Gunmetal Speedster

Pardon my ignorance for I am uneducated when it comes to this. But I was considering 4.10 gears for my car, if I bought what you just linked, would I be able to install the 4.10's in that and then just swap out the entire thing with what is on my car? Or am I looking at this wrong?

I went with the 3.91 gear set and glad I did. I didn't do the swap out, I had a local dealer do it. You need to be sure someone has the software to calibrate your speedometer. I didn't think this would be a big deal but the closest place I found that could do the calibration was in Cleveland and I live near Toledo.

Hopefully someone with 4.10 gear set will comment but keep in mind that your RPM's will be higher as you go higher with your gear ratio. At 70MPH my RPM's are 400 - 500RPM higher than the original gear set. If you have a 6 speed first gear doesn't even need to be used with my 3.91 gear set. You hit the gas and your RPM's shoot up fast, with a 4.10 gear set it will be even quicker. I have also heard the higher gear ratio you go with the worse your MPG gets. Personally I didn't buy my SS for fuel economy so using more fuel isn't a big deal to me.

[Gunmetal Speedster]

Originally Posted by OHIOSS

I went with the 3.91 gear set and glad I did. I didn't do the swap out, I had a local dealer do it. You need to be sure someone has the software to calibrate your speedometer. I didn't think this would be a big deal but the closest place I found that could do the calibration was in Cleveland and I live near Toledo.

Hopefully someone with 4.10 gear set will comment but keep in mind that your RPM's will be higher as you go higher with your gear ratio. At 70MPH my RPM's are 400 - 500RPM higher than the original gear set. If you have a 6 speed first gear doesn't even need to be used with my 3.91 gear set. You hit the gas and your RPM's shoot up fast, with a 4.10 gear set it will be even quicker. I have also heard the higher gear ratio you go with the worse your MPG gets. Personally I didn't buy my SS for fuel economy so using more fuel isn't a big deal to me.

I'm next to Cincinnati so I hope I wouldn't have to travel that far

But I definitely need something. My new cam has lost a lot of torq down low and between the bucking at or below 1500 it would be nice to upgrade. I'm hoping my local shop that did my cam can also do the gears as well as calibrate the speedo.

[CamaroFred]

Originally Posted by OHIOSS

...

Hopefully someone with 4.10 gear set will comment but keep in mind that your RPM's will be higher as you go higher with your gear ratio. At 70MPH my RPM's are 400 - 500RPM higher than the original gear set. If you have a 6 speed first gear doesn't even need to be used with my 3.91 gear set. You hit the gas and your RPM's shoot up fast, with a 4.10 gear set it will be even quicker. I have also heard the higher gear ratio you go with the worse your MPG gets. Personally I didn't buy my SS for fuel economy so using more fuel isn't a big deal to me.

For sure, a 4.11 is going to be a drag strip car.
With stock tire diameter it will still hit ~45MPH@6600. And you will need a shift to 4th to hit triple digits.

You can easily find the difference in MPGs. 4.11/3.45 = 1.19, so a 19% increase in torque and RPMs, 19% decrease in MPH/RPM and MPGs.

[christianchevell]

JRE billet caps BTW have to be machined to fit with the rear end removed completely by a machine shop supposedly, a 4.10 or 11 have been chewed up repeatedly over the years by those who posted as its the more gear teeth you have with the small size of our rear making it that much more prone to get chewed.... And also if running a true trac you use regular differential oil not the stock oil with modifier..... Just a few facts you may want to think of and it has to be set up perfect, there used to be a hot rod article about killer bee getting a true trac and 3.91s showing what a pro shop did, so buying gears is also usually a kit not just the gears. And installing a cam did not eat any torque BTW its just in the feel as it of course gained most likely all across the board unless its a crap grind compared to stock.