I have an offer to regear for an incredible price. I plan on getting 35s next and then beefing up the axle over the course of those 35s in preparation for 37s.

The problem right now is that if I run my 33s until they're bald, it'll be another 20-30k miles. I also drive 42 miles roundtrip for work mostly on the interstate, which is a 60 mph zone the entire time. I've seen the RPM chart, but I'm curious if anyone is running this setup and if it's something tolerable until I can get 35s. I understand first gear off-road can be a bit much for crawling, but fortunately for this situation I don't crawl. I'm just not wanting to be forced into the added expense of 35s or topping out at 55 mph on the highway. I also don't want this deal to expire long before it's time for 35s.

I've searched multiple forums for my answer and have really only found the question pertaining to the older 3.8. I know 4.56 isn't ideal for 33s, but are they at least temporarily tolerable?

 

You'll just be high revving for awhile gas mileage will go down but bearable if you don't mind those two things

 

Keep in mind that when looking at the gear charts, subtract about 1.25" from tire diameter to get a realistic RPM.

If you're not usually cruising 70, I think you're fine.

Why not just sell the 33s and get 35s now?

 

I don't know about tire shops in other parts of the country, but I was able to trade in my 33s when I bought 35s. I tried to sell them first and had no luck, so asked about trading them in at the tire shop. They gave me $100 each for the 4 half worn tires on trade and I even got them to give me $50 each for my 5 original wrangler tires . I traded 9 tires in on the 5 35s. I buy all my tires from this shop, a tire chain that is popular in the West, so that might have had a bearing on this.

I had been rotating my 33s myself, but the 35s or so heavy that I didn't want to man-handle them. Now I get free flat repair, tire rotation and balance at the shop.

 

I am thinking of going to 35's on my 08 rubicon auto 4 dr. so if I follow you correctly I should be looking at 33.75-34 tire size to be realistic in evaluating where my rpms will be ?

Is this because the diameter of the tire as stated by the manufacturer is actually smaller that the true diameter? or is there a different reason?

 

Partly because the tire is slightly smaller (actual diameter of a 35 or 315/70-17 can be 34.2-35, just depends on the tire). The other reason is you have to use the rolling radius from the ground to hub center. The squat in the tire reduces rolling radius, therefor effective diameter is smaller. You'll know what it ends up being once you recalibrate the speedo. For example, in my experience, a 315/70-17 Duratrac ended up with an effective diameter of 33.5" and a 37" MTR was 35.75".

 

I'm running 35 Duratracs on my 4:56's with manual. They actually measure out to just under 34". I do fine on the highway. 2500 rpm at 70 mph

 

What RPMs are you running at 80?

 

Just had 4:88's and Tru-tracks front and rear installed Friday All I can say is I finally got my 6th gear back after beak in at 75mph I was at 2850 rpm's with 315 duratracks.

 

Manual or auto... About to regear. Running the same tires. waffling between 4.56 and 4.88. I have a manual