Oversize Tires

I have a 71 that when I bought it has 33 x 12.5 tires. I was talking with a friend telling him I would like to drop the size down to say 30 x 9.5. He said the larger tire's could tear up the axel's or running gear. Is this or could this be true?

 

Yep. Driving habits are the critical variable here.

However, remember that this size is way larger than what was available at the time the Jeep was built, so you have to keep your expectations in check. A light foot and finesse will be your salvation.

 

What they said. I ran 33x12.50's for years with stock axles (44 tapered axle rear and 25 front) with few problems with a Buick V-6. I only upgraded when I started tearing up 25 spider gears doing stuff I shouldn't have anyway. Nickmil

 

Thank you for all that replied. Lynn I am going be looking for a later Dana 30 for the front, with disc's thinking this might be a easier to complete up grade verse looking for all the parts from various vehicle to complete. I guess unless I can get a good deal from the local tire shop as a trade I will keep the 33's since they are almost new.
I would agree also with you Glenn that the right foot can cause alot of damage.

 

I ran 33x15.50 TSL's on mine with no problem and I am not easy on it (put it this way last ofroad vehicle in 2 months I burnt it, broke 2 hubs, 2 driveshafts, complpetly busted the front spindle....) never had a problem, dropped down to 32x10.50's now because I hated the 12" wheels and dropped back down to 10's, will be replaceing the tires shortly with 33x12.50's

 

I run 32"s without any issue. Somebody correct me if I'm wrong, but your 71 should have a flanged Dana 44 in the rear which is darn strong.

 

Yep the 71 models had a flanged axle dana 44 which is basically the strongest axle put in a cj from the factory.

 

remember this: as you replace things (axle shafts, driveshafts, etc...) with stronger parts, then the more expensive things break (transmission, transfer, axle housings, etc...).

much better off in my view to keep the tire size under 33, as parts are less likely to break and if they do stock parts are cheaper to buy.

 

I’m running 33X12.5’s with a, modestly guestimated, 300 horse V-8 and my biggest problem has been with the spider gears on the stock Dana 25. Replaced the stock carrier with a Power Lok LSD and those problems went away.

It’s been my general experience when “bench wheeling” that griping has replaced actual knowledge of the subject. When someone doesn’t know better they’ll simpley claim, “Oh you can’t run those tires or your axles will go snapety snap.” The truth is you can break Rockwell axles with a 4 cylinder if you’re stupid enough with the loud pedal.

Your stock axles are a decent set, as mentioned before. With a stock motor and some common sense, they’ll probably do just fine with 33’s.

 

I run 35x12.5x15 Swampers on my '74.

If I didn't do really hard runs in the mud bog competitions around here, I bet my axles would still be in one piece! R) R)

Dmage so far:
1 outer shaft and u-joint on the front
1 twisted-in-half driveshaft tube
1 set of really smooth teeth on my Dana 44's spider gears

and the list will get bigger....

 

I haven't had any problems with my axles yet although I am not one to abuse my stuff.