I bought a set of NITTO Terra Graplers to go on my factory 20" wheels. The new tires were 305-55-20. Almost the exact diameter of the factory 275-65-20 tires, just a little wider.

The first set I had mounted and balanced by Pep Boys and after 3 times or them trying to get it correct, I then took my truck to a HUGE truck tire installer locally, who I know for sure that they know what they are doing. They said that all 4 tires were defective.

I set the tires back to NITTO and they sent me 4 new tires after about a week of arguing with them. The new tires were then mounted (Same size) and although they are a lot better, I am still getting a bad steering wheel shake at higher speeds. The original set shaked at all speeds.

I had my truck checked out by a mechanic and said that everything is tight and mechanically fine with the truck, and this makes sense because everything was fine until I changed tires.

My question is....I noticed after I bought the tires, it said the tires are recommended for 9-10" wheels. I believe our factory 20" wheels are only 7" wheels, could this be the problem? (They are not "bulging" at all.) And if not, what do you think could be the problem. I am out a lot of $$ now because of the tires and the additional mounting I have had done.

Sorry for the long thread....Mike

 

If you're mounting tires intended for 9-inch wheels on 7-inch units, yes, that could absolutely be the problem. In addition, you run a serious risk of the tire separating from the wheel, especially during cornering.

I'm surprised the tire store would even mount them.

 

I asked this same question before and everyone said no, it shouldnt be a problem. I even asked the tire place and they said no problem also. This is the only thing I can come up with.

 

tvsjr hit it right on. You should not have those tires on a factory OEM wheel. The manufacture puts those limits for safety reasons.

Either purchase new wheels for those tires, or go back to the original place where you purchased the tires...and get a refund or a tire that will work with your OEM wheels.

Sorry for the bad news...

Good luck!

biz

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2003 F250 SD SC 142" XLT FX4 V10 Auto 4x4 3.73s

 

I agree with you Pittsburg, the wheel width may not be in the spec'd range but the worst that'll happen is a "taller" tire with more crown to it. Desert racers (myself included) have been running tires wider than yours with wheels narrower than yours for years with no adverse effects (37-12.50-16 on 7" wheels on my truck). Better bead retention is the main reason, much cheaper than beadlocks.
OK I've never seen it done with 20's but shouldn't be any different.

 

the HD edition has 20" x 8" wheels according to the tire rack

 

the rim width difference shouldn't have an effect on the balancing of the tire. i myself and plenty of people i known have run under the manufatored rec rim width on the tires just fine on the road, all it does it buldge some. but as phydough said, it wasn't 20" wheels either, maybe the sidewall doesn't allow the flexibility with 20" rims as it does 16" rims?

 

thanks everyone! I used the problem as an excuse to buy some new wheels. Went with 20x10's. Moto Metal w/ a Black Power Coat Finish.

 

did that solve the issue?

 

Just ordered them tonight, so I will let yall know

 

When you get the tires mounted, ask for "match mount" preferred. Here is a quote of the web (easier than typing it all out)

Good luck with the new wheels...should look wicked cool!

biz

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2003 F250 SD SC 142" XLT FX4 V10 Auto 4x4 3.73s

 

any word ? Did the shakes go away?