you know theres a lot of mechanics where I am that say well.. let me start by stating my problem. Ive got a lot of mods added up and a built trans to take it. i run 31-32 inch AT's and dont plan on going bigger. I also have 3.55 gearing which is great on highway of course but sucks as far as any low end perf goes to the rear end. Theres two choices I hear of... 4.10's which some mechaincs swear by and some think its pointless. or 3.92's. I know i have the aerodynamics of a brick but perf is something I definatelty want. Im curious of the best gearing to improve low end, 0-60 acceleration and not tremendously hurt my top end. my transmission is already so built my engine hardly keeps up with the wider rpm band. top speed is 60 unless i took a roadtrip. i like to stomp it every chance i get, and im looking for mainly faster acceleration. Im gonna leave it up to you guys who (and theres a lot) who have re geared to either of the ratios and love it. thanks for the help and happy modding guys! also just curious if putting the HS 1.7 rr's would add at least another 500 useable rpm outta my engine. that would be another thing to consider as well. thanks

 

Go with the 4.10's. You will like them better.

The 1.7rrs won't allow you to rev any higher. In fact, it you might wanna reduce your redline some with them...... (couple hundred RPM anyway.) What they WILL do for you is give you more power throughout the engines useful RPM range.

 

I went from 3.55's to 4.10's and love the step up. I went Yukon gears and bearings and they are nice a a lot quiter than OEM. Now I know I have a different motor, but I lost like 1-2 mpg on the highway, but I gained a lot mpg at least in town! Actually if you look at it, it works out great. I used to get like 4-5 city if lucky, and the most was 15 highway, now I get like 10-12 solid.

I would not go with the 3.92's if I were you, your only talking a slight if in-measurable difference against the 4.10's, but regardless more power with the 4.10's.

 

alright i appreciate the help. ill go 4.10's . everyone here seems to have them..and never look back. Ive seen a lot of peoples trucks 0-60 improve with the gearing change. and 1.7 rr's ill have to give them a try. just heard to much negativity because im staying with 3.55's but its a terrible perf ratio. even hemi's have a 3.73 or 4.10 stock ratio I believe. as far as higher rpm band. id guess a top end build such as heads and cam are the best option. im just really wanting to improve my 0-60. 7.5 sec is a hell of an improvement from when this truck was all stock but dosent seem to quite be fast enough lol. I can sacrifice 1-2 mpg lol. looks like ive got my next summer projects in line to save up for. just ordered some black side steps and led tails here. modding is addicting.. as ususall this forum has helped me tremedously. i like it

 

oh and how much would gearing cost front and back. parts only obviously. i dont skimp quality on my truck. I also dont like a huge dent in the wallet.

 

I have 4.10s and like them quite a bit. My gas mileage is always consistently just below 12mpg with the 5.9L. Mixed highway and city driving. Make sure you get the speed-o corrected as well. If not, your mpg calculations will be off, among other things.

Stop by Randy's Ring & Pinion for prices. Google it.

 

I paid $1400 plus tax, but that was a good deal as my parts are more expensive because I have a dana 70 and dana 60. I would shop around and get a good deal right now. Problem is a lot of shops won't work on them because doing it is so hard it's out of their comfort zone. Your better of finding a Mopar enthusist with a lot of experiance. And make sure when you pick it up the gears are quite. Be real nice to it for the first 500 miles, no long drives and let it cool between trips. I would say nothing over around 20 miles on the freeway, and stay under 65. They get hot as they are setting.

 

okay good to know. i know some old timers (experienced and trusted mechanics) who would do it. and will I loose performance at higher speeds. say stomping at 60 or 70 im guessing its way better at lower speeds but dissapates at higher speeds. and ill definately go easy on them. do you get the fluids changed after 500 miles? kinda like a new engine or transmission. so 1400 about in parts plus labor.... hmm might do a motor build first if its almost the same price. im guessing easily 2k after labor. plus possible maintenance after 500 miles.

 

ill check it. i will have to recalibrate the speedo for gear changes? i thought that was for tires and lift only.. hmm. guess i learned something new. thats more $ mods arent cheap after intake, pcm, and exhaust ha.

 

Cheapest place for Yukon I've found is completeoffroad.com. I paid 600 for front and rear gears and timken install kits along with a rebuild for my LSD. Total in mine was around the 2k mark as well.