Thread: any dramas using a different sized spare?

yeh I was say you couldn't use it as your diff i would imagine would not appreicate such differences unless you could match the rolling diamenter with pressure in the tyres...........that would be my guess.

Best to change both tyres (front or rear) if you are in a jam and need to use a different spare. My trailer tyres on 16" Rangie wheels are 225/75R16 and on the Fender 235/80R16 and while the wheels will fit and are similar the over all rolling diameter is different. So if I had a drama on the Fender and used the spare and had that fail I would take 2 wheels off the trailer (trailer spare and one of the wheel on the trailer) say it was rear LH and replace both rear wheels and put the odd ones on the trailer as it will not hurt the trailer. Safest way with minimal impact on your diffs and trans. Should be OK running different sizes front and rear for a short time but never one side only.
Cheers
Craig

I wouldn't run different tyres at any time.If you can't afford 5 muddies you can't afford any,a 29'' tyre on one side and a 32'' on the other will destroy your diff in a very short space off time. Pat

Originally Posted by grover7488

hi

does anyone have any ideas on what would happen if you had a spare that was say a 32" muddie (810mm OD) and your other tyres were 29" roadies (735mmOD)?
If you got a flat could the spare be used in an emergency or would this do some damage to the running gear?

cheers

you can use it in an emergency to get a few k out to the road for example, but with the LR centre diff setup, you are better having very similar rolling radius tyres across each axle, and preferably all around...

some sizes give very similar rolling radii even though they have different descriptions

eg, with 265/75/16 you can use a 235/85/16 or even a 7.50 X 16 to get you out of trouble

i can afford the five mudies (barely!). it was just a hypothetical question as i wondered what would happen if you left the oversized spare on whilst back in the city and happened to puncture the **** "road" tyres. (another situation would be if you destoyed two of your muddies while on the trail and were hanging with guys running bigger tyres as to whether you could use one of theirs to get you going). I know that from my Pootrol owning days you could stick the odd one on the front and the stubby lever in 2H and be on your way (a bit lop-sided of course)

Not a real problem doing this on road, but off road with centre diff engaged would be a no no.

I've driven about 100k's on bitumen with a 29" spare on. All the rest are 31's. Had no probs.

Then again, I've also driven 1000k's with the CDL on (accidently) and had no probs with that either, apart from weird tyre wear.

Must be lucky. DL

Originally Posted by numpty

Not a real problem doing this on road, but off road with centre diff engaged would be a no no.

Many cars have space saver spare wheels which are a different diameter and width than the normal road wheels. An open diff would hardly know the difference and would be fine, a locker/LSD would be a different story. If you have standard diffs and dont engage the center diff lock on hard ground you will be fine.