Mismatched small spare tire on an 80. Effects? (1 Viewer)

[jamisobe]

I didn't bother to read all the posts, so flame me if need be.

If you can't afford a real size spare to match your 33's, I doubt you'll be able to afford the work to fix any possible damage caused by running a tire 3" smaller than the others. I know there is more "tech" to a 80 than a AWD Subaru/Audi, etc, but on those cars, running different sized tires can fry the axle diff/viscous coupler, so I don't see why we can't resonably assume that where possible, we should try to treat our 80s with the same level of care (bombproof nature of the 80 aside).

It is ridiculous to go out with a temporary solution that might cause your rig serious harm.

My recommendation? Call around to tire shops and find a used 33" tire that will fit on your rim. Set your budget at $80 (or $40) and just do it. I think the peace of mind here is worth it.

Next time maybe you should try reading the thread before you throw up.

 

[S.CarolinaFZJ80]

I'm pulling my 305 75 R16 BFG MT's half tread on 4, 5th is brand new!

If you are interested...

 

[eurorom]

How about 4 of the Hankook Dynapro Mt in 315/75-16 ( 34.8" ) vs spare 295/75-16 (33.6" )
I can not fit a 35 in the stock spare location and I do not want a rear bumper yet! no space inside the cabin and too heavy ( 35 ) to carry on rack!


Your thoughts!

 

[Brian Macgyver]

When I ran open trucks, and even racing buggies, I took pains to be sure that all wheels were the same diameter. I have run 2wd & 4wd in racing. I always made sure that the spare was the correct diameter to protect the differential in any case. The differential is an expensive piece of equipment. It is one of the most costly parts of an off-road racer, or your truck, if you are lucky enough to have lockers.
But at the time, I was just racing those vehicles, not running them daily. What did I know about everyday use of normal trucks? In racing, overstress of differentials was the main cause of failure for off-road racers.
When racing, we might have been able to afford to blow up diff's. But can you? Yes... Your spare must be the same diameter as the tire that it replaces!! It may be narrower, or wider, but the diameter should be the same. If it is not, you will be in deep crap!!
Trust me. A stressed out diff will not make you a happy man!

 

[46/71 Hybrid]

How about 4 of the Hankook Dynapro Mt in 315/75-16 ( 34.8" ) vs spare 295/75-16 (33.6" )
I can not fit a 35 in the stock spare location and I do not want a rear bumper yet! no space inside the cabin and too heavy ( 35 ) to carry on rack!


Your thoughts!

I checked on the truck that I referenced in my previous post and it's still running strong, and currently on permanently mismatched tires. The CD is always locked and 42,000 miles later, the truck is still running strong with no breakage related to the mismatched tire. Take it for what you will but if the truck has run 42K with no problems on permanently mismatched tires, I have to believe that you can run 100-200 miles on mismatched tires while you're looking for a tire shop/replacement tire.