18” wheels 17” spare

[Xyleff]

my wheels are 18” and spare is 17”. Would it be any issues or damage if i had to use the spare?

 

[RamDiver]

my wheels are 18” and spare is 17”. Would it be any issues or damage if i had to use the spare?

Provided the wheel circumference and bolt patterns match, no problem. There are many online calculators.

AFAIK, most 17" rims have a 5-bolt pattern (usually on gen 4) and most 18" have a 6-bolt pattern (usually on gen 5).

I've heard of exceptions to the norm but haven't seen any myself.

Tire Size Calculator

The best tire size calculator. Use our tire size calculator to find tire size specs and suggested tire sizes. Then check prices for all available tire sizes.

tiresize.com

 

[Xyleff]

Provided the wheel circumference and bolt patterns match, no problem. There are many online calculators.

AFAIK, most 17" rims have a 5-bolt pattern (usually on gen 4) and most 18" have a 6-bolt pattern (usually on gen 5).

I've heard of exceptions to the norm but haven't seen any myself.

Tire Size Calculator

The best tire size calculator. Use our tire size calculator to find tire size specs and suggested tire sizes. Then check prices for all available tire sizes.

tiresize.com

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Both have the same bolt pattern. it’’s about 1.5” difference between the two based off those tire calculators. That wouldn’t cause any damage?

 

[KKBB]

If that is what ram put on it, use it. If it is a different wheel and tire than what came with the truck off the assembly line, then you might want to change it back.

 

[Green_Manalishi]

It won't damage anything. The wheels turning at different speeds is no different than driving on a curve.

 

[18CrewDually]

Wheel size doesn't matter. The overall diameter of the TIRE is what needs to match.
So, If the 4 18" wheel tires measure to be 31.5" then the spare needs to be 31.5".

 

[ThunderMug95]

i still run the spare my truck was born with. Oem wheels were 17” with 265/70’s. I am on 35’s now, so about 4” in diameter difference. My plan was to use that spare on the front, even if it meant double the work. I also run with a compressor and a plug kit.
I do not hardcore offroad…
Am I wrong thinking the front with 4wd disengaged is safe for limited distance?

 

[Xyleff]

If that is what ram put on it, use it. If it is a different wheel and tire than what came with the truck off the assembly line, then you might want to change it back.

It’s factory. But i changed to aftermarket wheels.

 

[Xyleff]

Wheel size doesn't matter. The overall diameter of the TIRE is what needs to match.
So, If the 4 18" wheel tires measure to be 31.5" then the spare needs to be 31.5".

so it would be an issue running what I currently have then because they’re not matched up in that aspect.

 

[Xyleff]

i still run the spare my truck was born with. Oem wheels were 17” with 265/70’s. I am on 35’s now, so about 4” in diameter difference. My plan was to use that spare on the front, even if it meant double the work. I also run with a compressor and a plug kit.
I do not hardcore offroad…
Am I wrong thinking the front with 4wd disengaged is safe for limited distance?

This is exactly what my concern is.

 

[18CrewDually]

The main concern at any distance, is on the rear axle with anything other than an open differential. If you have an open differential it won't hurt anything short term to get home.

 

[ThunderMug95]

This is exactly what my concern is.

So the front is an open diff. The 4wd actuator engages/disengages the CV axles to receive the T-cases power. The front driveshaft isn’t engaged in 2wd mode. With this logic, having mismatched front tires will not affect the drivetrain.
Yes, yes, alignment and handling etc, but were talking about emergency use. Pretty confident given my set-up is very capable in 2wd.
Someone correct me if my logic is flawed please.

 

[KKBB]

Personally I think it would be fine. I checked mine a few months back. I have 20" wheels on my 2500. The spare is 18". I'm not sure how close the tires were in size when there was no wear, but the spare is almost 1.5 or 2" taller than my 4 tires on the truck due to wear on them. I assume the manufacturers know there will be wear on actual tires used vs the spare. Not sure how much of a difference would be too much though.

 

[Xyleff]

So the front is an open diff. The 4wd actuator engages/disengages the CV axles to receive the T-cases power. The front driveshaft isn’t engaged in 2wd mode. With this logic, having mismatched front tires will not affect the drivetrain.
Yes, yes, alignment and handling etc, but were talking about emergency use. Pretty confident given my set-up is very capable in 2wd.
Someone correct me if my logic is flawed please.

I’m thinking that same logic as well. So in an event i needed the spare, keep it on the front.