Air down to match the spare?

[NoMoFoMoCo]

It just occurred me... since the spare doesn't match the size of the 4 working tires, couldn't you just change out the flat and then air down the other 3 tires to match the height of the spare? This would be a temporary, low speed workaround, obviously.

 

[SD Rebel]

It just occurred me... since the spare doesn't match the size of the 4 working tires, couldn't you just change out the flat and then air down the other 3 tires to match the height of the spare? This would be a temporary, low speed workaround, obviously.

How much smaller is the spare tire? I think they are classified as full size, even though they aren't exactly the same size. It that's the case, the wear on the differentials would be negligible even at speed. I think the 1500 spare tires are designed to allow even towing at 50 mph or slower.

I would also say be very cautious of driving on the highway with underinflated tires, it is the leading cause of tire failure.

 

[HeavyMetalHauler]

How much smaller is the spare tire? I think they are classified as full size, even though they aren't exactly the same size. It that's the case, the wear on the differentials would be negligible even at speed. I think the 1500 spare tires are designed to allow even towing at 50 mph or slower.

I would also say be very cautious of driving on the highway with underinflated tires, it is the leading cause of tire failure.

Think the spares are 18 inch

 

[SD Rebel]

Think the spares are 18 inch

Gotcha, but the tires? For example, the Rebel has the largest diameter wheel/tire package on any RAM (besides the TRX) at 33". The 2nd largest is the 22" wheel & tire package, which is 32".

Even if you have 20" or 22" tires & an 18" spare, I would compare that with the spare tire size (not wheel size) and see how close they are on a online calculator, here is a good one: https://www.tacomaworld.com/tirecalc?tires=295-65r18-275-60r20

For example: at 295/65-18 is slightly larger in diameter than a 275/60-20, though both technically 33" tires.

 

[LaxDfns15]

For the Rebels you get 275/70R18 tires on the wheels, then a 275/65R18 spare, which is 1" diameter smaller. Completely stupid. If I had to drive on the spare before I can replace it I'd probably put it on the front axle instead of the drive axle.

 

[SD Rebel]

For the Rebels you get 275/70R18 tires on the wheels, then a 275/65R18 spare, which is 1" diameter smaller. Completely stupid. If I had to drive on the spare before I can replace it I'd probably put it on the front axle instead of the drive axle.

I got together with another 3 Rebel owners and we bought a set of Rebel take-offs from Craigslist, then split that set up among use for full size spares. Ended up costing us $250 each, but not bad for a new 33" tire and OEM wheel.

I did that specifically for off-roading purposes, I have the OEM spare still in place and take the Rebel spare with me as a full size off-roading spare, so I can still keep going if I get one flat. If I get a 2nd flat, that will be my sign to head home.

But in terms of highway driving, I think the 1" smaller spare isn't an issue, especially since the Rebel doesn't have a limited-slip differential. Just as long as you us it as a spare and change it as soon as reasonable. But if you have to drive a while before you can replace, then I would probably switch to the front like you mentioned.

 

[LaxDfns15]

I got together with another 3 Rebel owners and we bought a set of Rebel take-offs from Craigslist, then split that set up among use for full size spares. Ended up costing us $250 each, but not bad for a new 33" tire and OEM wheel.

I did that specifically for off-roading purposes, I have the OEM spare still in place and take the Rebel spare with me as a full size off-roading spare, so I can still keep going if I get one flat. If I get a 2nd flat, that will be my sign to head home.

But in terms of highway driving, I think the 1" smaller spare isn't an issue, especially since the Rebel doesn't have a limited-slip differential. Just as long as you us it as a spare and change it as soon as reasonable. But if you have to drive a while before you can replace, then I would probably switch to the front like you mentioned.

Right, I wouldn't do much driving on it if at all. If I off-roaded more heavily I would definitely have a full size spare, but at this point I'm going to wait until I change tire sizes and just bite the bullet to buy 5.

To answer @NoMoFoMoCo, I would NOT air down my tires to try to "match" the diameter. Just don't put the mismatched tires on the drive axle.

 

[SD Rebel]

Right, I wouldn't do much driving on it if at all. If I off-roaded more heavily I would definitely have a full size spare, but at this point I'm going to wait until I change tire sizes and just bite the bullet to buy 5.

To answer @NoMoFoMoCo, I would NOT air down my tires to try to "match" the diameter. Just don't put the mismatched tires on the drive axle.

On a side note, if you have an America's Tire / Discount Tire in your area, they can offer their road hazard warranty and lifetime rotate & balance on tires you didn't even buy there, just as long as they don't have too many miles on them. I brought in my RAM at around 1000 miles, and I got the whole package for $120.

Not only will this save me from the $49 dealer rotation (which don't even balance) at every 5000 miles, but will replace a tire should it not be repairable. Just one Duratrac tire cost almost double the whole package. Also, they fix tires for free just as long as they are repairable.

 

[brian42]

The donut should still be the same circumference regardless of what it looks like so you shouldn't have to air down to use it.

'Emergency Use Only' will come with it's own limitations since it's not a regular tire but rotational size shouldn't be one of them.

If you are concerned you can put a regular tire in its place. The ORG comes with a full-size spare (regular tire on an 18" steel wheel) so you can fit a real tire under there if you want a better option than the donut your truck came with.