How much difference does 0.5" make?

[PaulSula]

I am starting to do research for some new tires. I know that my stock 16" rims are only 7.5" wide. I could fit a 285/75/16 BFG KM2 because the minimum rim width according to BFG is 7.5"

HOWEVER...what I want to find out is about 305/70/16s. BFG says that the minimum wheel width is 8". A mechanic friend has told me that minimums are made for a reason, however I REALLY don't want to spend money on new wheels.

THE QUESTION: How bad would it be to run a 305/75/16 on a rim that was 0.5" less than the minimum recommended wheel width? Thanks guys.

 

[Richard_]

I run a 12.5 on a 7 inch rim with no problems

 

[PaulSula]

Richard, thanks for the reply. Is that against the tire manfacturer's guidance? How long have you run this set up? How about on-road / off-road manners? Do you get a lot of sway from mounting a large tire on a small rim?

Does anyone else care to weigh in on the subject?

 

[Absolute]

i am running 305/70/16 on my stock rims... love it, no issues

 

[daPitbull]

I'm running beadlocks now, but I've run 12.5"w tires on 7.5"w wheels before with no problems.

 

[gm350reratliff]

Its .25" on each side of the rim. I think you will be fine.

 

[PaulSula]

It seems like no one can think of a reason not to mount the 305's on a 7.5" rim. I'll do it! (Eventually)

Thanks for the help fellas.

 

[rook]

I looked into this.. only the opposite situation. I was looking at 275's fitting a 9" wheel. The tire shop I spoke with told me it can be done but that some tires may show extra wear on the edges if mounted on too wide a wheel. I suppose the opposite would happen - wearing in the middle if mounting on a narrow wheel.

I believe the wheel width range is set by the tire mfr. for ideal treadlife and safety, but a half inch will not make a huge difference. Many offroad rigs run wide tires on narrow wheels to prevent the bead from breaking when aired down.

 

[fourwd1]

Mounting a tire on too wide or too narrow a rim will affectthe wear pattern, but I certainly would not worry about .5"

 

[SKIDPLATE]

You have to always take in account that a manufacturer will tell you only what will keep them out of court. Just like the timing belt replacement recommendations. They have to account for the absolute worst situations. So yeah, if you live in the Alaskan outback with -80deg winters, you should probably replace your belt after 90k miles. Same goes with tire recommendations. Anything in moderation will probably work just fine.

 

[PaulSula]

Thanks for all the advice. Now, I'm working to wear out these tires so I can get the new ones.