Confused on tires for 1999 TJ Sport

[jnofsinger]

Hello everyone,

I recently purchased a TJ and love the thing. It has the dana axle 99 6.0 cyl manual. Been replacing the normal things such as water pump and found this forum a great resource. The only thing I am still confused about are the tires.

I currently have 265/70/15 on the Jeep. From every calculator and thread, I have found this isn't an optimal tire size for the Jeep with it being mostly stock. I do like the tires they drive fairly well on the road but will rub on a full turn of the steering wheel. My questions are

Am I losing power and mpg with the current larger tires?
What tires are a bit of a better fit that still maintain the chonky look? or would an offset adjustment be ok (not sure what that would be though)?

Assuming the stock size was 215/75/15 and playing around with the calculator from 1010tires.com the 265/70/15 is pretty far off for mph and revs per mile. Guess at the end of the day I am still looking for a chonky tire, but without the rubbing and potential power/mpg/mph issues, even the 275/60/15's on the calculator seem like a better fit.

Anyone's thoughts/ideas/pictures would be awesome and thanks in advance for the help!

 

[Rickyd]

Look at the tag on the rear diff. If it says 3.07,not 3.55 or 3.73 you want something small like a 235/75r15. If you regear or find some 3.73 or 4.10 axles you could run 31s comfortably. Bigger tires will rob a small amount of mpg's if you have correct gearing. Much more if it is geared to high

 

[CharlesHS]

If the tires rub against the control arms or inner fenderwells when turning the steering wheel lock to lock; you can loosen (may need to grind tack weld) the steering stop bolt on the steering knuckle and back out the bolts a couple turns to reduce or remove the rubbing of the tires.
IF the tag is missing you can determine the gear ratio by chocking the front tires, jacking up the rear differential, placing the transmission or transfercase in neutral, place a chalk or crayon mark on the driveshaft and tire, rotate the tire and compare how many times the tire rotates to how many times your rear driveshaft rotates. This will provide an approximate on what the differential gear ratio actually is.
Once you have determined the tire size you want and the gear ratio installed in the differentials; you can calibrate (do a search online for tire size to rear drive gear ratio) the speedometer/odometer with a replacement drive gear in the transfercase output housing (easy replacement).

https://images.app.goo.gl/XYpWCEYVg7quC2KN6

 

[jnofsinger]

Thank you both for replying so quickly. From the picture here it appears to be 3.73 ratio it was a bit dirty... that might explain why the larger tires seem to ride ok?

When I was under there looking around, I see there are wet spots on like something seeping (it is not dripping) from around the axle area. Should I be concerned? I don't hear anything grinding but would rather avoid doing damage especially if it is just a seal or bearing that might need to be replaced.

 

[TheBoogieman]

Dana 44 with 3.73 gears. Clean all the grease/oil off everything (Parts/brake cleaner) and see where the leaks are coming from. Start cleaning the rust off and stopping it too.