31" BFG MT's

[2001ExpSport]

Today I recieved my tire and wheel package from National Tire & Wheel. Being new to this style of tire I am a bit unsure what to expect. I have a few questions for you seasoned mudder owners. At about 5-10 mph I can feel a slight 'wobbling' sensation, but it goes away after I pass 10 mph. On the highway at about 65-75mph it is very shakey. The tires have already been mounted and balanced and currently have 35psi in them. I checked all the tires and they look ok, no visual mounting problems. I am not even close to a tire expert so I really don't know what to look for. Is this 'wobbling' a charateristic of a mud tire or is it slightly out of round? If so, I need to contact NTW to get a new one sent. Also, is the highspeed shake a charateristic or is there a possible balance problem?

This is my first set of mudders so bare with me if these are silly questions.

I never expected these tires to act like my stock Wilderness tires, just don't know what is normal and not.

P.S. How do I get this blue stuff off?

[Edited by 2001ExpSport on 08-25-2000 at 08:16 PM]

 

[4x4]

not the tires

If you and I understand "wobble" the same way you have some other problem. I am currently running 32/11.50x15 BFG MT's on a 1994 F150 with 101,000 miles. My ride is very good with little noise and only the very slightest vibration (probably from mud in the rims). I think you must have a bad component somewhere. It may be a rim or tire or some front end parts. I've also run 16" MT's on a 3/4 ton Ford with no ill effects. I'd get it checked out as soon as I could.

 

[2001ExpSport]

You said in your post title that it's not the tires, but then you said, "It may be a rim or tire or some front end parts."

I didn't have this problem until I put the muds on.

[Edited by 2001ExpSport on 08-25-2000 at 08:24 PM]

 

[RangerX]

Get the balance checked. They may not be as balanced as they could be.

 

[wade]

hot water and an SOS pad
sounds like something is out of round,a bad tire

 

[Tom Wilk]

I'm with Rangerx, have them rebalanced first. Also, try dropping the pressure to around 30 psi. I would think that the MT's would be slightly noisier and would have some weird characteristics, but they shouldn't wobble or vibrate. Also, retorque your lug nuts to make sure they are at the proper torque. According to Chilton's, the lug nuts should be tightened to 100 ft.lbs.

Get some Westley's "Blech-White" and a large brush to clean off the blue stuff.

 

[4x4]

OK, Not normal for the tires

What I'm saying is the tires them selves will not do this unless one or more is defective.

 

[2001ExpSport]

Ok, I made some rounds with a pressure guage and found them all to be different, 32, 35, etc. So, I set them all to 30psi. The ride is better, the wobble is noticable sometimes. It sort of comes and goes. The vibration at high speeds cycles thru 65-80. What I mean is, it comes and goes while traversing though that speed range. The vibration is not that bad, but it is noticable. Enough to shake the passenger seat and the steering wheel, but it is very slight. From 10 to 65 it feels fine, very smooth. I inspected the inside of the tire and rims and noticed that there was only one large weight on the inside and no weights on the inside towards the middle of the rim for outside balance. Do you guys think this might also be a problem? I like the rebalancing idea, I really don't want to have to send these tires back, I really like them.

If the tire was out of round, wouldn't it vibrate and any speed? I know I could always call National Tire, but I wanted to get some advice first so that if they tell me that it's normal because they don't want to send me a new tire I will have some recourse.

I will talk to them on Monday and see what they suggest. Thanks for you help guys!

 

[2001ExpSport]

Ok, I narrowed it down to one tire by rotating them. Also put on Monroe Reflex shocks and the shake is almost gone. Now I believe it is a balance problem because it only happens above 65mph.

One thing that I did that seemed to help the problem go away was that I put on my stock lug nuts instead of the ones they supplied. The tires ride much better now and I had a tire shop look at the nuts. They said they were the wrong ones, so I trashed them. I will be getting the trouble tire rebalanced tomorrow.

Thanks for all of your help guys!!!

 

[donkey boy]

I'm with the others regarding the high speed shake: this is not normal. A slight vibration at very low speed, less than 5 mph, that I experienced with all my MTs.

The blue stuff. Normal soap and maybe a pressure washer is enough.

Be sure your stock lug nuts fit correctly (length, shape, etc) If they sent you the wrong ones, make them send you the correct ones It's a bad idea to use incorrect lug nuts!

[Edited by donkey boy on 08-29-2000 at 06:52 AM]