Gear recommendations

[scguy]

Long story short:

 

LWB MJ. 4.0 HO, AW4, 4.5" lift, D30, 8.8 (going in), 32s. 

 

I'm trying to decide between 4.10s and 4.56s. Don't plan on doing much interstate driving. 4.10s would be a close equivalent to stock ratio, (27" and 3.55) 

 

How much will I regret it if I go with 4.10s over 4 56s? My main goal is to be able to drive 55-60 in 4th with the TCC locked at a reasonable RPM. 

 

I know 4.56s would make it more fun around town, which is mostly where I drive. 

 

 

Planning on going with Revolution gears unless someone has better suggestions. Yukon is just $$$

Thoughts?

[derf]

I run 265/75R16 tires on my XJ which are about 32"

 

I have 4.56 gears and really like them.  They're good overall.  Good around town and not too much on the interstate.

[Smokeyyank]

4.56, motive gears are decent. Really they are all the same in a different box. 

[ghetdjc320]

4.56 here also. I’ve been running al things revolution since the came out. Used superior before that. Gears setup very nicely. 4.56 is great all round. Excellent on 33’s and even decent in 35’s. 

[Eagle]

4.56

 

[89eliminator]

4.56 especially if you think you'll run bigger tires in the future.  

[Jtrux]

4.56 for sure.

[WahooSteeler]

4.10s and 32s are nearly identical in the RPMs/speed as stock tires and 3.55s, as you've already pointed out. Just me, but even if you're only on the interstate occasionally, 4.56s are turning a lot more RPMs and I'd think fuel mileage will take a decent hit.  If you're not wheeling it hard and don't think you'll go up in tire size later, 4.10s seem to be the match. But as always, personal preference.........  

[Pete M]

12 hours ago, WahooSteeler said:

4.56s are turning a lot more RPMs and I'd think fuel mileage will take a decent hit. 

 

the equations for mpgs is more complicated than just rpms.  it'll be ok.    heck, the stock 2.5L/auto came with 4.56s on those tiny tires.  

[ghetdjc320]

16 hours ago, Pete M said:

 

the equations for mpgs is more complicated than just rpms.  it'll be ok.    heck, the stock 2.5L/auto came with 4.56s on those tiny tires.  

Agreed, surprisingly I’ve actually gained MPG’s going with 4.56 over 4.10 on 33’s. The 4.0 torque is down low but a little higher rpm seems to get it to peak efficiency at cruising speed (which I haven’t seen in a long time here in island lol) 

[scguy]

I did end up going with the 4.56 gears. Got all the tools and parts on the way or here, so here I go in the slowest way possible.

[ghetdjc320]

3 minutes ago, scguy said:

I did end up going with the 4.56 gears. Got all the tools and parts on the way or here, so here I go in the slowest way possible.

 The trick with gears is just to think in 3d. Think about adjustments on all 3 axis then just add the necessary preload.