Making a JKU fun in the Highway (speed) parts of an Expedition?

[eternus]

I'm running 33" Terra Grapplers and have 0 armor on it at this point. If 3.73 is having a hard time pushing 33" tires in a JKU with no load past 65 then anything will be an upgrade. I don't know enough about swapping out gearing, but it sounds like I can't just find someone that re-geared their Rubicon and buy some 4:10s for cheap because I'll need a D44 up front to hold that set... they won't fit in my default D30. So... it's not really a cheap direction to go by any stretch. I hope to put on 35s when I wear these tires out which will make this whole thing even messier. It looks like I might just be moving over to Tacoma land if I need to re-evaluate the vehicle I'm in anyway.

Hey DTD, yup... in Longmont. I see the link to Rocky Mountain Overland in Tom's sig, glad to see a local Overlanding group, may have to stop by there and say "hey!"

 

[eternus]

The D44 on the Rubicon is a bigger, tougher pumpkin and I think thicker/stronger axle housings. I know I'd need D44 to go up to 37" tires so... there has to be something going on there.

 

[DallasJKU]

I run the 2.5 " MC with OME and 37" KO2's on my Rubicon. I feel I have adequate power and it rides really well when its not windy. The wind really degrades the driving experience and sometimes I just avoid the highway when its that windy. I'm thinking adding the tie rod and drag link from MC soon.

 

[ExplorerTom]

The normal D44 is stronger all around. But from what I've heard, the axle tubes in a JK D44 still need to be sleeved or trussed to prevent them from bending. And the outer Cs are known to bend as well. A trussed or sleeved D30 with the Cs gussetted with 4.56-4.88 gears should handle 35s no problem. My front axle is just what I described with 4.56 and 33s. I can run 75 no problem.

And the Rocky Mountain Overland is a good group. We have a get together the second Tuesday of each month in Arvada. We have all sorts of people/vehicles (Tacos, JKs, Land Rovers, Land Cruisers, Explorers.....). A few come down from the Longmont area. Sign up on the forum and say "hi".

 

[lysol]

If you just want a D44 that you can throw on some 33's and or do some mild wheeling, grab someone's stock front D44 off a Rubicon that already has 4.10 gears in it. If you don't already have a D44 rear, just grab a used one as well hopefully with 4.10 gears.

From my personal online research, the issue resides in the front D44 and not the rear D44. I am leery putting on 35's on my stock Rubicon D44 axles. The rear D44 seems fine for that tire size and mild wheeling, but the front D44 seems to have issues related to the axle shaft, axle housing, the axle "c"s, and the ball joints. You could re-inforce the axle tube with some sleeves and/or a truss (though a good welder is needed for the truss or otherwise, your axle housing could be destroyed), the "c" with gussets, the axle shaft with decent aftermarket shafts, and the ball joints with aftermarket ball joints..... Or you could go purchase an aftermarket D44 housing and build it up. Endless options, but all costing a lot lol.

 

[eternus]

Well, I got out on the highway today and really don't seem to have a problem at 75 and up to 80 even... not sure where I got it in my head. It's really the solid axle that makes it a bit squirrely feeling... but driving that thing sure does make me smile. My wife has been a heavy influence in trying to make me think I want a truck... but I think I'm going to at least make it through another summer. I like the smiles on my kids faces when driving around with the top & doors off. I'll just look into a good rack for hauling things. I think the 3.73 is probably just fine and I'll stop blaming it on my highway blues. The truth is that I just want it to feel like our Outback when I'm on the highway... you know, you're headed down the road and when you look at the speedo you realize you're doing 90. That's never gonna happen in a Jeep (and most likely never in a Tacoma either.)

 

[eternus]

I think I'll hold off on the D44 and higher gearing until I've paid the thing completely off and got my other mods in place... there is a good chance I'll end up getting rid of it in a few years and making a Tacoma into an overlander, then get an older Jeep for fun.

 

[Comanche Scott]

I think I'll hold off on the D44 and higher gearing until I've paid the thing completely off and got my other mods in place... there is a good chance I'll end up getting rid of it in a few years and making a Tacoma into an overlander, then get an older Jeep for fun.

I think that is a great plan. :victory:
Except I wouldn't put much more into your JK, unless you get some extremely awesome deals. Mods are about forty cents on the dollar at resale, and that is only if they are house hold name stuff.
It's money you could use to pay off the Jeep early. That would also save you interest.
Then you roll into the Tacoma in a good position.

I had an '09 4 door 4wd Tacoma. It was a great vehicle. :beer:

 

[jsek29]

Check your gear ratio

Did you re-gear your Jeep to get 3.73? They came from the factory with 3.21 gears, except the Rubicons with their 4.10 stock gearing. I know that our '07 Sahara with 3.21 and 33" tires was nearly worthless at freeway speeds. I would think a change to 4.10 or 4.56 would do you wonders on the freeway and the trail.

 

[eternus]

I have the towing package which upgraded it to 3.73.

Honestly, after spending time on the highway today, I think it's really not as bad as I had remembered it. I take backroads to work and generally don't see speeds over 65 more than once a month, if not longer. (c: I suppose that further suggests that I shouldn't really care about highway speeds since I rarely deal with them.

I'm going to finish my Metalcloak upgrade by putting some OME shocks in and see if that makes it even better than the rubicon shocks with Metalcloak springs.

 

[jsek29]

Sweet! If speed/power does continue to bug you, keep that re-gear in mind.

I'm interested to hear how that goes. We're putting the Metalcloak Overland Elite 3.5 lift on our Jeep, which is best for our use. Please post up your thoughts on your Metalcloak system once you get it installed.

 

[harv3589]

The D44 on the Rubicon is a bigger, tougher pumpkin and I think thicker/stronger axle housings. I know I'd need D44 to go up to 37" tires so... there has to be something going on there.

The 44 has the same tubes and C's as a 30 unless u get the HD one which has J8 tubes...that's not factory on a rubicon. The pumpkin is bigger only to house the larger ring and pinion. If u want a factory 44 then get the one with the J8 tubes otherwise it's not much of an upgrade. Even then u may want to look at trussing and reinforcing the C's....if ur pockets r deep then look at the Dynatrac HD housing...

If ur not a hard core off roader then I wouldn't bother changing the 30 out...I'm just leaving mine in, doing a regear to 4.56, ARB locker, axles, ball joints, truss it...probably get the gears cryo treated which increases the strength of them significantly.

 

[Kmrtnsn]

Have you reflashed to account for the 33" tires? Do you have a Procal or a Flashpaq? If you have not reprogrammed your shift points, this is probably 80% of your problem. Having a similarly equipped Jeep I am not having the problems you are having, even when I am in CO or UT. I have noticed that my power response is sluggish above 10K feet and do intend to re-gear from 3.73 to 4.56 at the end of the year.

 

[kojackJKU]

KMRTNSN, You nailed it with the flashpaq. I noticed a big difference when you recalibate for the tires etc. I love my flashpaq and it works awesome for all kinds of stuff.

 

[eternus]

I've had the 33"s on since I got it and the speedo has always been correct. I'm mostly sure they flashed it properly at the dealership before I got it (the dealership also does tons of custom builds and have a full "off-road" team.) The FlashPaq is cheap enough these days it might be worth getting anyway, I planned to get one before my next tire purchase because I planned to go up to 34" tires.