Can stock 06 Rubi LJ axles handle 35" tires? Would an axle upgrade be needed?

**CB3** · 08-14-2008, 01:49 PM

I'm curious. I currently have 33 X 10.5 R15 tires and intend to stay with that size, but always in back of my mind I flirt with putting on 35's.

I'm getting regeared next week to 4.88 diff gears (auto tranny with 0.69 OD). If I need to upgrade axles (in case I want 35" tires in future), this is the time to do it.

So I wonder if stock axles could handle 35's if I ever upgrade tires? to 35 X 10.5 R15 or R16 tires (yes I know where I can get that size tire).

Also, would a 4.88 regearing be low enough for 35" tires with 0.69 OD auto tranny? If not, I guess there's always stroking engine to 4.6L (someday).

Scotch740 · 08-14-2008, 01:59 PM

Here is a great gear ratio calculator, for side by side comparisons.
http://www.grimmjeeper.com/gears.html

I think you will be fine with the D44s and 35"s.

Lawrence · 08-14-2008, 02:17 PM

Quote:

Originally Posted by CB3

I'm curious. I currently have 33 X 10.5 R15 tires and intend to stay with that size, but always in back of my mind I flirt with putting on 35's.

I'm getting regeared next week to 4.88 diff gears (auto tranny with 0.69 OD). If I need to upgrade axles (in case I want 35" tires in future), this is the time to do it.

So I wonder if stock axles could handle 35's if I ever upgrade tires? to 35 X 10.5 R15 or R16 tires (yes I know where I can get that size tire).

Also, would a 4.88 regearing be low enough for 35" tires with 0.69 OD auto tranny? If not, I guess there's always stroking engine to 4.6L (someday).

You'll love the 4.88s with 33s, that's what I run and it is great. You really feel the difference up long grades and mountain roads. Before going back to 33s, 4.88s were fine with 35s, but lacking a bit IMO. If you plan on 35s, consider 5.13s instead.

Depends what you do, no problems, just don't do anything stupid. I ran 35s on stock axles for 3 years without problems. You could always get alloy shafts, keep your stock as spares, and call it the day if it make you sleep better at night.

**CB3** · 08-14-2008, 02:54 PM

Mountain roads on and off the freeway are common here. I live in the Cascade Mountain range (Pacific Northwest portion of Rocky Mountains) and there is also a smaller coastal mountain range here. We have a level stretch of I-5 for about 30 miles, but that's the only level freeway for hundreds of miles in either direction.

There is one 7% freeway grade near hear (not I-5 but another freeway) that has a 7% grade sign on it. My LJ Rubi without regearing can barely pull the hill in 3rd gear with OD off, and it's difficult to get up to the speed limit of 55 mph (freeway entrance ramp is at bottom of the hill) and difficult to hold that speed. There are even steeper freeway grades than that around here.

My XJ with 4L and stock gearing and 30 X 9.5 tires used to go up those grades in 4th gear with ease, often with torque converter still locked up. It could pass nearly anything on the road.

Now, to my shame, my LJ Rubi was passed by a Toyota Prius going up that 7% grade the other day. I'm sure we were both floored out, full out, and he passed me with ease. It was humiliating and frustrating. Well, I can at least still pass most motorhomes (eyes rolling) and most grandmas, but only because the grannies let me. Their little rice burners could blow my LJ Rubi off the road anytime they wanted.

Hopefully regearing will solve my frustration and humiliation. If not, I'm getting another XJ. But I'll try regearing the fat LJ Rubi beast first to see how much that helps. I guess I'm sticking with 33" tires, after considering these issues. Besides, my brakes are good now, but if I upsized tires to 35", I'd have to upsize brakes to Vanco or something similar. I'll stick with 33s and 4.88s.

kman8 · 08-14-2008, 03:24 PM

Quote:

Originally Posted by CB3

my LJ Rubi was passed by a Toyota Prius going up that 7% grade the other day. I'm sure we were both floored out, full out, and he passed me with ease. It was humiliating and frustrating.

**CB3** · 08-14-2008, 03:25 PM

Where did you get 32 X 10.5 BFG ATs? I didn't know they made that size.

**CB3** · 08-14-2008, 03:27 PM

Quote:

Originally Posted by kman8

I could see the tree hugging liberals in the Prius laughing their asses off too. It gave them much joy to outpower a known gas hog.

It's bad enough to get substandard gas mileage compared to just about every other model of modern vehicle (even after I've improve my gas mileage with several mods), but to also be outpowered by a gas mizerly pious Prius is more than I can bear, especially when its full of tree hugging hippie liberals blowing me off the road and I can see them laughing as they pass me. Oh the shame!

My XJ could have properly terrorized them driving circles around them on the pass at freeway speeds (literally if I wanted to). The struggling, bogged down, lugging LJ Rub just made them laugh that smug, self satisfied, condescending laugh that liberals in a Toyota Pious do when they pass your gashog.

imbezol · 08-14-2008, 03:56 PM

Quote:

Originally Posted by Lawrence

If you plan on 35s, consider 5.13s instead.

He can't gear his front D30 over 4.88.

xulcuz · 08-14-2008, 04:01 PM

Quote:

Originally Posted by imbezol

He can't gear his front D30 over 4.88.

I think he has a Rubicon so it would have a 44 in front as well...

**Jerry Bransford** · 08-14-2008, 04:01 PM

Quote:

Originally Posted by imbezol

He can't gear his front D30 over 4.88.

His Rubicon's front axle is a Dana 44.

imbezol · 08-14-2008, 04:02 PM

Quote:

Originally Posted by xulcuz

I think he has a Rubicon so it would have a 44 in front as well...

Ahh.. so he does. I've read too many 4 cylinder gearing question threads today.

RVA_TJ06 · 08-14-2008, 04:02 PM

Quote:

Originally Posted by imbezol

He can't gear his front D30 over 4.88.

OP, the guy has a rubicon. D44's.

elkfan2 · 08-14-2008, 04:05 PM

Quote:

Originally Posted by imbezol

He can't gear his front D30 over 4.88.

Read the post it's a rubi so yes he can because it's got a front dana 44. To answere the OP's question the stock axles will be fine for the trails around the pacific northwest, hell i ran 35's on factory dana 35 axles (for almost 2 years) before upgrading to a dana 44.

Lawrence · 08-14-2008, 04:14 PM

Quote:

Originally Posted by imbezol

He can't gear his front D30 over 4.88.

In case you missed it, he has a Rubi, so he can...

Lawrence · 08-14-2008, 04:24 PM

Quote:

Originally Posted by CB3

I guess I'm sticking with 33" tires, after considering these issues. Besides, my brakes are good now, but if I upsized tires to 35", I'd have to upsize brakes to Vanco or something similar. I'll stick with 33s and 4.88s.

Like I mentioned before, I went back to 33s and I couldn't be happier. For me, 35s required the Vanco kit as my TJ wouldn't stop and a steering upgrade to eliminate the tendency to be all over the road at freeway speeds. Now, offroad it just takes paying a bit more attention to the trail and picking the right line, it is much easier on my components, and I don't have to "jump" in the Jeep anymore.

33s and 4.88s is a darn sweet combo with the 4-speed auto. You'll be blazing by those Priuses and regain your pride.