Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: Kermit on January 20, 2011, 08:04:09 PM

Title: Axle ratio with 35s
Post by: Kermit on January 20, 2011, 08:04:09 PM
What gear sets are you guys running with the 35"wheel/tire size?

6 th gear is useless and it doesn't crawl even in low range without mega clutch action IMHO
(http://img.photobucket.com/albums/v618/RRJR/jeep6.jpg)
Title: Re: Axle ratio with 35s
Post by: specialk on January 20, 2011, 08:11:08 PM
4:10 at the moment.  Want to go to 5:13 at some point.
Title: Re: Axle ratio with 35s
Post by: hps4evr on January 20, 2011, 08:11:38 PM
with that engine i think a 4.88 would be a good swap. i talked to a guy a while back that did 5.13's and he said the rpm's were pretty high on the highway. but, he did have an auto. your sixth gear may be fine at highway speeds with 5.13's. might want to find a JK website where a few guys have tried different ratios. you'll have to consider new differentials at the same time.
Title: Re: Axle ratio with 35s
Post by: rws on January 20, 2011, 08:14:01 PM
I have 4:56's with 35's.   Wish I had 4:88's.

Tanny is an AX-15    5-speed
Title: Re: Axle ratio with 35s
Post by: w squared on January 20, 2011, 08:20:31 PM
For  JK with a 6 speed, 4.10's are okay...4.88's will get you back to where 4.10's and 32's will put you.

Honestly, 4.10's are a wee bit tall for 35's. If you're going to stick with 35's I'd say Heeps is right. I'd go with 4.88's.
Title: Re: Axle ratio with 35s
Post by: Kermit on January 20, 2011, 08:30:37 PM
you'll have to consider new differentials at the same time.

?? :o??
Title: Re: Axle ratio with 35s
Post by: stroker sahara on January 20, 2011, 08:53:20 PM
I run 4.10s with 36s. I have a 4.6 stroker and a T18a tranny. In 4th I am at 2500 rpm at 100 and have plenty of gearing down in low. You have overdrive, so I would think 4.88 would be sufficient. The lower the ratio, the weaker the pinion as it is smaller with less teeth.
Title: Re: Axle ratio with 35s
Post by: Tyn Pow on January 20, 2011, 09:42:44 PM
I think he's just referring to the fact that you have a D30 up front and the deepest gears available are 4.88.  If you wanted to go deeper you'd have to swap in a 44, 60, etc.  Your rear diff might also have ratio limitations depending on your model.
Title: Re: Axle ratio with 35s
Post by: FiEND on January 20, 2011, 10:29:43 PM
dana 30 can go to 5.13 and has been able to for a few years now.

4.88 w/ 35" here w/ NV3550 5 speed.  it's pretty decent on road, trail and highway.  only way i would go to 5.13 is taller tires or stop being daily driver.
Title: Re: Axle ratio with 35s
Post by: Rubi03 jef on January 21, 2011, 12:26:42 AM
4.0 with a 6speed and 5.13's and 35's

crawling is a beautiful thing . no issues with anything . can climb straigh up walls in 2nd and just letting the clutch out no gas needed

on the highway is another story im at 3000rpm at 105 km so it sucks for long distance

you complain about your 6th gear being useless now     i complain about my 12st gear being useless
i start in 2nd gear at every light and have no issues what so ever

so 4.88 are probably your best bet ..  i plan on going to bigger tires so 5.13's are ready for my future upgrade
Title: Re: Axle ratio with 35s
Post by: Tyn Pow on January 21, 2011, 10:59:19 AM
dana 30 can go to 5.13 and has been able to for a few years now.

Didn't know that so I just checked it out, Richmond only makes them to 4.88 but Yukon actually goes all the way to 5.38.

I'm planning on 5.13 or 5.38's with the fullsize diffs, but on a 36-37" tire.  On 35's I think anywhere from 4.56-5.13 would be good depending on your use, DD or wheeler.
Title: Re: Axle ratio with 35s
Post by: Marco on January 21, 2011, 11:38:30 AM
i have a tired 4.o in my tj with 4:11 (dana44's) and my new 37's and i like it fine. it would be a bit more user freindly if it was a bit lower though i guess.good enought for me considering price to regear. my 0.02
Title: Re: Axle ratio with 35s
Post by: Kermit on January 22, 2011, 04:05:40 PM
Thanks... 4.88s it is......start saving again
Title: Re: Axle ratio with 35s
Post by: Spinalguy on January 23, 2011, 08:43:48 PM
i have a tired 4.o in my tj with 4:11 (dana44's) and my new 37's and i like it fine. it would be a bit more user freindly if it was a bit lower though i guess.good enought for me considering price to regear. my 0.02
i used to say the same thing on 37's. Than i went to 5.13's and i can not believe i ever told anyone that 4.10's and 37's were ok. ;)
Title: Re: Axle ratio with 35s
Post by: AstraX on January 24, 2011, 05:57:01 PM
considering price to regear

What is the cost like to regear?  The gears themselves don't seem overly expensive, labour costs pretty high on a job like that?
Title: Re: Axle ratio with 35s
Post by: FiEND on January 24, 2011, 06:03:10 PM
gears + setup kit is usually around $300 per diff ($600)

labour would prob be $300 or $400 per diff.  more or less depending on if and type of locker intalled etc.  ie.  ARB may run $500 for first diff and $400 for second..  detroits or spools probably cheaper.

that's about what I would expect to pay someone.  some may be more, some less.
Title: Re: Axle ratio with 35s
Post by: slimbeam on January 24, 2011, 07:34:27 PM
Ive had 3.55 with my 35's for a number of years with my 4.2 and did ok, 4.56 is whats in her now and is better for climbing and 5th gear is used again
Title: Re: Axle ratio with 35s
Post by: Rubi03 jef on January 24, 2011, 11:37:49 PM
with a good choose or tools and some common sense and the internet  a person can do anything

but if you dont feel adventurous then you will be spending probably 400- 500 per diff to have gears installed plus the cost of gears and the install kit

Title: Re: Axle ratio with 35s
Post by: AstraX on January 24, 2011, 11:45:05 PM
well some day I might feel adventurous but for now my jeep is still under warranty so if I did do anything to it in the short term it will likely be done by licensed mechanics.  Though I don't know how much of a difference that makes when it comes to warranties.
Title: Re: Axle ratio with 35s
Post by: Canuck Bob on January 31, 2011, 06:01:39 PM
I found this graph a great deal of help.

http://www.experimentalinsanity.com/vehicle/resources/gearratios.php
Title: Re: Axle ratio with 35s
Post by: Rubi03 jef on January 31, 2011, 07:05:12 PM
thats an awesome ratio chart .. one problem   with it is   it doesnt take in consideration for the engine .. 4 banger or 4.0 L    or the few people that are running hemi's

but besdies that its a good chart
Title: Re: Axle ratio with 35s
Post by: allanbr on February 01, 2011, 10:19:35 AM
Kermit, if you want, I can send you an Excel spreadsheet that you can plug in various trans - T-case, axle ratios and tire sizes and then see the final gear ratios of each. It also shows the vehicle speed @ various engine RPM's and also RPM's @ 110kph for the top three gears.  I'd post it on here, but unfortunately, I'm not tech savvy that way.  I'm pretty sure I could attach it to a PM though.

Let me know - I've found it useful for deciding on future parts purchases.
Title: Re: Axle ratio with 35s
Post by: Kermit on February 01, 2011, 05:40:11 PM
Yes please.. PM sent
Title: Re: Axle ratio with 35s
Post by: specialk on February 02, 2011, 07:29:49 AM
Here is the spreadsheet.