I recently bought a set of 33x12.50 Baja Claws and I love them, but the 3.21's in my diff's have got to go. I'm not planning on going to 35's anytime soon and since I drive a ton of highway miles (I have the 6-spd) I've been trying to find a set of used 4.10s. I've been looking for a while and I'm not having much luck at all. I ran across a website called Just Differentials and saw that they have 4.11's for our jeeps.

I just wanted to know if anyone else has ordered from that site and if I were to order from them, what all would I need to install the gears. They offer 4.11's reverse cut for the D30 and 4.11s standard cut for the D44. Also, they have the standard open carrier for sale that I would need for the D30. Am I missing anything else besides the install kits for both? Oh and do I need a standard install kit that runs about $100 or do I need a "master" install kit that's more expensive around $200?

Sorry for all the questions. Just thought I'd try and get everything covered in one post. Thanks for all the input!

 

I don't know anything about that website. but just a reminder, when you buy used, it's an "as of" sale, so you can't expect to get a return or warranty should anything fail...

 

I just ordered all of the above parts you mentioned except install kits from Just Differentials. I dealt with a guy by the name of Jason I can give you his ext. if you wanna get in touch with him, super nice guy to deal with and he seemed to be pretty knowledgeable when it came to JK's. The 4.10's and front carrier are Dana/Spicer OE JK parts which is partly why I ordered from Just Differentials. Preferably I would have ordered from a forum sponsor but any of them that carry 4.10's carry the Alloy USA brand and didnt have any in stock because Alloy USA 4.10's are backordered until the end of next month. thats info I got directly from Alloy USA. If you have over 25 000 miles on your JK you might want overhaul kits, dont quote me but I think they include new pinion and carrier bearings. Also it depends who's doing your install if its someone who has alot of experience they might be able to re-use those bearings. If you ever plan on going to 35's you might want to go with 4.88's, then again I know alot of people who run 35's on a 6 spd with 4.10's and they have no complaints.

 

I'm not one of them. I am only marginally happy with the 4.10s and 33s. Around town no problem. Typical Oklahoma highway driving they're .. okay. Throw in some wind or a grade, and it sucks bad. I hate when some butt-hole in a Harley-Davidson F-150 POS tailgates me at less than five feet when I'm trying to pass someone at 75 MPH and b-hole supreme just won't give me a break. There just isn't any "oomph" to make the push when you throw in a grade and wind. And this is with a six speed. If you have an auto, the situation is even worse--go lower even. If I was paying someone to install the gears, I'd buy 4.88s for 33s or for 35s (since the 4.56s are nay impossible to find). The gear cost is insignificant compared to the install cost. And, although I've done all the work on my Jeep thus far, and have a fair amount of shadetree mechanic's experience in my six decades on planet Earth, I wouldn't attempt a gear install myself unless I was with someone I trusted to do the job right.

 

Thanks for the input guys. I think I'm going to go ahead and order those parts from JustDifferentials. I know I'm not going to throw 35's on there for at least another couple years and for the amount of highway driving I do I think 4.10's will be a good balance. Adam, if you don't mind giving me that Jason guy's extension I'd appreciate it. In case I have some questions and what not, it'd be nice to a number to call. Thanks

 

Look in the for sale section, there is a guy with 4.10 that wants to trade for 3.21 because he is regearing anyways. Might be worth a shot

 

So you can imagine how I feel with 3.21's and 33's, 6th gear is useless and 5th can maintain speed on an incline MOST times. I feel like 4.10's are going to put me where I want to be and give me a good balance between power and mileage, that and they're a factory/OE gear set which for whatever reason makes me feel a little more comfortable than going with 4.88's etc. FWIW one or two of our forum sponsors have 4.56's in stock or at least they did a cpl of weeks ago.

 

I just put 4.88's on TODAY with 33's that are down to 31.9". It is a TON better, though I am rolling 3100 RPM's at 75 MPH. I would not get 4.10's. If you are going to spend the money, I would get 4.88's if you have a true 33, or maybe 4.56 if you have a 31.9" 33. I think you will be disappointed in a 4.10 gearing.

 

 

My Duratracs are, according to my math 33.16"? I've crunched all of the numbers in my head over and over, spoken with my installer told him what I wanted and what I use my jeep for he recommended I go with 4.10's as well. I want stock performance back plus some without sacrificing too much fuel mileage and the 4.10's put me right where I want to be. I've driven a 4 Door Rubi and a 4 door Sahara with 6 spd, 4.10's and true 33's and they were more than noticiably better than what I have now, especially on the highway lol. The 4.88's and even the 4.56's are overkill for what I need really, would be nice to have if I wheeled more though.