Jackass Sluggish with 30/31s?

[Umbra]

Some of you beat up on Project Jackass about the 18 inch JK wheels he is currently sitting on.
You old women know who you are (Jackass is looking for YOU Chris) and have nagged me into submission.

I took Jackass out for about a 50 mile drive today and he seems a tad sluggish. I assume it's because the wheels/tires are roughly equivalent to 32s and the factory rear end doesn't like those wheels any more than you guys.
(Side note: The speedo read 60 mph and I was actually running 72 )

I intend to take Jackass in for alignment since the lift stuff is all gone and now would be a good time for the canyons and new tires.

I like the look of the canyons with 31s and search tells me they're OK for the factory suspension.

BUT, Jackass is a "work/woods/lake/snow jeep" so I'll be on the interstate and pulling a light trailer once in a while and I need all the HP and torque the 4.0 produces.

Experiences?Ideas? Suggestions?

Stock tire probably best but...well you know.

Thanks

 

[Rob5589]

Gear swap.

 

[Umbra]

What's best?

 

[TJScott]

I stuck 4.56 in mine. But, I'm running 33's. For the most part I like it. But, I still struggle on the big hills. Guess it's a weight thing. My top speed now is about 80 at just above 3k. I know that sounds fast for a Jeep. But around here, 80 is the flow on the freeway. 5th gear was all but useless before the gear change.

BTW I loved your posts when you were working on jackass. Very amusing.


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[JMT]

32's need at least 4.10, 4.56 ideally. What is your gear ratio? 31's work well with 3.73

 

[Umbra]

I stuck 4.56 in mine. But, I'm running 33's. For the most part I like it. But, I still struggle on the big hills. Guess it's a weight thing. My top speed now is about 80 at just above 3k. I know that sounds fast for a Jeep. But around here, 80 is the flow on the freeway. 5th gear was all but useless before the gear change.

BTW I loved your posts when you were working on jackass. Very amusing.


Sent from my iPhone using Tapatalk

Thankya sir...more to come on the build thread. Jackass is here at the house now so some cosmetic and metal work starts soon.
I'm having fun on that thread.

And thanks for the response.

 

[Umbra]

32's need at least 4.10, 4.56 ideally. What is your gear ratio? 31's work well with 3.73

I'm guessing it's the 3.73 stock gears, no evidence of a change. And it sure feels slow. Had to shift down to third to maintain 60-65 on a big hill.

 

[Kyle_W]

I'm guessing it's the 3.73 stock gears, no evidence of a change.

I have 3.73 gears and 33" tires (however, soon I am going to switch to 31" tires). I can pull a small 6x10 trailer no problem; with it I can feel a very slight loss off "umph" when I step on the gas.

When I pulled a big 8x12 enclosed trailer though, that was a TERRIBLE. Never, ever, ever again.

 

[bobthetj03]

A 30x9.50x15 tire came stock on mine. I'd run that. I had 3.73 gears.

 

[xxdabroxx]

What transmission do you have?

 

[Umbra]

5 speed.

I am leaning towards 30s, just for practicality.

 

[xxdabroxx]

I'd think a 30" tire would work fine with 3.73 gears.