Full time 4x4 can a 33 work as a spare????

[ntx78k5]

I have a 78 with the full time 4x4 I can never remember what TCase that is but I am running 35's with a 4" lift. I carry an old 33" spare as that is all that will fit inside in the normal carrier.

My question is can I even use that 33 if I get a flat without screwing up something in the drive train?

Eventually I mount a spare tire carrier on the back bumper that will hold a 35 but until then it it even worth my time carrying that 33 around?

Thanks,

 

[divorced]

NP203

I would run a 33 for a spare, it's better than nothing. Don't put your t-case in the "LOC" position though.

 

[4GUNZ4X4Z]

NP203

I would run a 33 for a spare, it's better than nothing. Don't put your t-case in the "LOC" position though.

Yep, what he said. You'll be fine as longs as you don't have your axles locked or spooled. I carried a 33 as spare for awhile and used it a few times while runnig 36's.

 

[surpip]

it wont matter if the tcase in in lock, the only think that matters is if he has some sort of locker

 

[ntx78k5]

All good news, and thanks for the info. I just run it in normal 4 wheel. In fact I've only moved it to 4 wheel lock once and that wasnt even 4 low.

 

[divorced]

it wont matter if the tcase in in lock, the only think that matters is if he has some sort of locker

The t-case could be considered a front-to-rear locker, and with a smaller tire on one corner of the truck it will make the driveshaft for that axle spin at a different speed than the axle with the same size tires. The difference in size isn't very much though so maybe it wouldn't have any serious negative effects.

 

[surpip]

hummmm ya i guess that makes sence, it would make the driveshaft spin a little faster/slower. that would not be good

 

[4trolls]

not to sound like a dumb ass but ,with a locker couldnt you let the air out of the 35 until its 33" tall?

 

[trailblazr81]

not to sound like a dumb ass but ,with a locker couldnt you let the air out of the 35 until its 33" tall?

I wouldnt want to drive anywhere at any real speed with a tire aired down. I live in Hollister, maybe 8 miles from "Hollister Hills" SVRA, and I wouldnt want to do the few miles of 55+ MPH with a tire aired down to be same height as another. And how would you do it? Eyeball from one side of truck to the other??

 

[4trolls]

the spare is not on the truck so you could put it right next to it, and close enough should be good enough for a spare.....I would think

 

[mikey_d05]

Maybe I'm way off base here but my common sense meter tells me that even if you aired down a 35 to the height of a 33, it would still have a larger circumference due to the fact that the tire is simply bigger...that being said, yes, a 33 will work fine for a spare in a pinch.

 

[Scrubby]

Even if the case is in LOC, won't the open differential handle that one wheel spinning faster and not affect the drive shaft speed? That's what differentials do. They allow one tire to spin faster than the other.

 

[pvfjr]

The open diff would make up for half of the difference, not all of it.

I've driven 15 miles at 55+MPH on 5 PSI in 36" radials, would do it any day. Sometimes that's just where the nearest gas station is.

 

[divorced]

Even if the case is in LOC, won't the open differential handle that one wheel spinning faster and not affect the drive shaft speed? That's what differentials do. They allow one tire to spin faster than the other.

Think of it like running 31's in the front, and 44's in the rear - only not as drastic. The differential in the axle will balance the difference from left to right, but not front to rear.

 

[Scrubby]

Think of it like running 31's in the front, and 44's in the rear - only not as drastic. The differential in the axle will balance the difference from left to right, but not front to rear.

Ahh. I see now what you mean. The diff will equalize the axle, but that still might be a different speed from the other axle.

 

[trailblazr81]

If I had a locker I would go with same size tire. I wouldnt want to have to worry about the bad things that can happen with an under inflated tire at highway speeds. Generates heat and then possible tire failure. If the axle isnt locked I would have no problem using a 33" tire as a spare. As long as the other tire isnt bigger than 37".
Oh and about having the tire off the truck to check size with the tire on the truck...with the truck weight the tire could loose an inch of height. But hey, you do what you want and I will do what I want and we will both be happy,