Putting new Tires On Now What About Gears?

[carcandy]

Ok, So two weekends ago I got the RC 1.25" body lift done. I already have the level done. Everything is ordered now I'm just impatiently waiting. On order is:

35x12.5r17 General Grabbers
KMC XD Endura 125 17x9 0mm offset 5" Backspace
And new shocks (Skyjacker M95's)

Hopefully this all gets here this week. Now once this is all on how important is it to upgrade the gears? I believe I have 3:55s right now. I'm only 2wd and I don't have Posi. I wouldn't mind eventually upgrading to Posi and taller gears.

What route should I go? Gear sizes, Brands, Etc? Any input would be appreciated.

 

[monettejb]

You most likely have 3.21. I did which is why I got such good gas mileage in my 2wd vs my 4wd. I have 3.55's in my 4wd. I doubt you'll have those in just the 2wd. You are deff going to want to regear at some point just dont know how much is might cost for parts and install if it'll be worth it. Im thinking 3.21's is going to suck with 35's as I have 3.55's and Ive heard that 35's suck with those. But you get mixed reviews with everything so who knows.

 

[carcandy]

You most likely have 3.21. I did which is why I got such good gas mileage in my 2wd vs my 4wd. I have 3.55's in my 4wd. I doubt you'll have those in just the 2wd. You are deff going to want to regear at some point just dont know how much is might cost for parts and install if it'll be worth it. Im thinking 3.21's is going to suck with 35's as I have 3.55's and Ive heard that 35's suck with those. But you get mixed reviews with everything so who knows.

I just checked. The sticker on my axle definitely says 3:55, so not as bad as 3:21's but might still suck.

 

[monettejb]

Good deal, one of the lucky ones. I had 3.21 and was really bummed out. I know you feel somewhat relieved.

 

[Hemi450hp]

With you being a 2011, you have a few options on gears. The only limited slip unit available for the 2011-up ZF axle is the factory LSD. These usually run around $500. From there, you can either run the factory 4.10 gears that come in the RT trucks, or buy aftermarket and have the carrier machined to accept the aftermarket ring gear. The factory 4.10's are $359, whereas the aftermarket are $195. The kicker is going to come down to labor...how much is it going to cost in your area and do you trust the shop that is about to drill into your new carrier.

 

[smiley]

35's and 3.55's = dog getting going. 4.10 would be nice in there.

 

[mattman_13]

3.55s with 35"s really isn't that bad in my 5.7. Definitely tolerable. Interested to see how the 4.7 pulls em!

 

[Hemi450hp]

3.55's are more designed for 33" tires and smaller...4.10's would be perfect for the 35's, and then 4.56's if you plan to go up to 37's. The hemi will definitely turn 35's with 3.55's, but it gets so much better with 4.10's or 4.56's.

 

[carcandy]

Well, the tires came in today, and I gotta say I think they look awesome! Now the wheels need to hurry and get here.

I think I definitely want to step it up to the 4:10s, I don't ever plan on running anything bigger than the 35's so that should do fine.

 

[carcandy]

With you being a 2011, you have a few options on gears. The only limited slip unit available for the 2011-up ZF axle is the factory LSD. These usually run around $500. From there, you can either run the factory 4.10 gears that come in the RT trucks, or buy aftermarket and have the carrier machined to accept the aftermarket ring gear. The factory 4.10's are $359, whereas the aftermarket are $195. The kicker is going to come down to labor...how much is it going to cost in your area and do you trust the shop that is about to drill into your new carrier.

Is this something I can get from you? Or would this be a dealer kinda thing. I almost purchased the wheels from you, I was going to go with procomps. I changed my mind at the last minute though, and you didn't carry KMC. Let me know. Depending how crappy these run I might want this sooner than later.

 

[4x4Hemi]

damn those are purdy! i like the red letters quite a bit!

 

[Hemi450hp]

The tires look awesome. I can get everything for you. Factory 4.10 Gears are $359, Factory LSD is $509, and the Bearing kit you need is $95.99...shipping is free. I don't have the gears or LSD listed on the site just yet, but I will work on that tomorrow.

 

[brightwhitesport]

Yea, I'm curious to see those mounted hurry!

 

[carcandy]

Thanks guys, I'll get pics up as soon as I get them on.

 

[carcandy]

The tires look awesome. I can get everything for you. Factory 4.10 Gears are $359, Factory LSD is $509, and the Bearing kit you need is $95.99...shipping is free. I don't have the gears or LSD listed on the site just yet, but I will work on that tomorrow.

I was just browsing Summit Racing and they have an Auburn Limited Slip unit that says its for the 2011 & 2012 P# 542070. Can you get that? and would that accept aftermarket gears?

 

[Hemi450hp]

That is the Auburn unit for the old 9.25". We sell a lot of them for the 2010 and older trucks, but it will not work on the 11's and 12's. Summit probably just didn't realize they changed the rear diff in 2011.

 

[carcandy]

Well, I've had the tires on for about a day now. Been driving around town a lot and I gotta say the 3:55's with the 4.7 aren't near as bad as I was expecting. I do have the Bully Dog Tuner on now so that's probably helping although its on the fuel efficient tune. I think the shift points are way better than stock. I still do wanna upgrade to a posi unit eventually and I might as well go with 4:10's at that point. All in all I'm very satisfied.