4.27s with 35s?

[Jesse J]

I am looking for some opinions on running 35s on 4.27s. Stock 4.0 with ax15. I have a rear axle with 4.27s and a tru trac and the front doesnt have a carrier or gears so it would be cheaper up front to put 4.27s in and not touch the rear axle but also it would be better to just get the ratio I want the first time. Not a designated trail rig but it will see offroad a lot. Thinking about a true trac up front as well

[Pete M]

which axles are we talking about?  not all ratios are available for all axles. 

[Jesse J]

waggy d44s 4.27s are available 

[89 MJ]

I’d run 4.56 if it were me. My truck on 31s with 4.10s turns about 2700 rpms at 75 mph. At that speed and rpm fuel consumption is about 3.5 gph. 4.56s on 35s would be similar to that. 
If you won’t go that fast very often though or live in hilly regions, I’d run 4.88s. 

[89 MJ]

My dad has a YJ on 35s with 4.10s and a 5.3. He says that sometimes he wishes he put 4.56s in that. 

[Jesse J]

15 minutes ago, 89 MJ said:

I’d run 4.56 if it were me. My truck on 31s with 4.10s turns about 2700 rpms at 75 mph. At that speed and rpm fuel consumption is about 3.5 gph. 4.56s on 35s would be similar to that. 
If you won’t go that fast very often though or live in hilly regions, I’d run 4.88s. 

I was since the beggining planning to run 4.88s but it's costly. but the rear is set up already with 4.27s so it would be cheaper and easier but maybe I should just bite the bullet

[Jesse J]

ok going 4.88s and another true trac  up front. That should be good right?

[MiNi Beast]

1 hour ago, Jesse J said:

ok going 4.88s and another true trac  up front. That should be good right?

Yep.  Run it. 

[75sv1]

A few things. First try and separate people with auto trans info from manual trans. Also, what is your plans, ie offroad, mixture, DD and some weekend trails? Also, even as a DD, I'd think about terrain or hills, vs mountains, vs flat land. I think there are some 4.30 gears for Dana 30's. You do have to look. 

    Look here for a calculator:

Gear Ratio Calculator (grimmjeeper.com)

     I do run two XJs. One is on 31's 3.73 and on 32.5's 4.10s , both autos. Both do OK on flatland. Both a bit sluggish in mountains of WV. the 32.5 was on 31's and it ran good in the Mountains. It did have issues before I bored the TB though. I do run about 2000 rpm at say 60 mph, and 2200-2300 at 70 mph. I plan to run 33's on my MJ with 4.10's and a manual trans.

[Jesse J]

2 hours ago, MiNi Beast said:

Yep.  Run it. 

badassery

[MiNi Beast]

Badassdor! 

[Jesse J]

ordered . aint cheap but buy once cry once

[ghetdjc320]

5 hours ago, Jesse J said:

ordered . aint cheap but buy once cry once

 4.88’s are great. 4.56 with an ax15 with stroker on 35’s was also nice but I could definitely have used 4.88’s though and that’s with plenty of long highway drives, 

[ghetdjc320]

By the way, here are the gear ratios for the AW4:

2.8

1.53

1.0

.75

 

AX15

3.83

2.33

1.44

1.0

.79

 

The unique thing to remember with an automatic is the torque converter, which in effect produces a sort of lower version of each gear. Top end highway speeds are very similar with both options. In practice, they both have a very similar effective first gear as well when the torque converter is factored in. Both are great tranny’s for our Jeep’s imho. 
 

 

[Jesse J]

1 hour ago, ghetdjc320 said:

 4.88’s are great. 4.56 with an ax15 with stroker on 35’s was also nice but I could definitely have used 4.88’s though and that’s with plenty of long highway drives, 

awesome 

 

1 hour ago, ghetdjc320 said:

By the way, here are the gear ratios for the AW4:

2.8

1.53

1.0

.75

 

AX15

3.83

2.33

1.44

1.0

.79

 

The unique thing to remember with an automatic is the torque converter, which in effect produces a sort of lower version of each gear. Top end highway speeds are very similar with both options. In practice, they both have a very similar effective first gear as well when the torque converter is factored in. Both are great tranny’s for our Jeep’s imho. 
 

 

thanks AX15 should be coming out of the cherokee this weekend!