darrenb

ok, so these new sumitomo st908 tires i am waiting for to come in are speed rated at a "sad" 65 mph. with this rating being for a commercially weighted trucks, will it be safe to take the truck at speeds higher than this? my thinking is that because i am running well below the weight rating of these tires, it should be safe to travel at higher speeds than indicated??????? can someone please enlighten me on this??????

RyeThomas

The tuff part is getting them balanced properly. Ive had mine up to 85-90 mph plus for extended periods of time no worries. The funny part around here if you get on 95 and dont do 75-80 youll get run over even in a big truck so the speed rating on the tire goes out the window when tractor tailers are on your rear doing 80+. You will be fine.

CSAKing

did you have to do some kind of lug conversion kit to run "big rig" rims???

ryfrat

If you have a dually all ready they make a 8 to 10 lug adapter.about $800.00

JP-4.5

I wondered about the speed rating also. I have 19.5" rims and tires on my truck and the tire is rated for 75 max. Bridgestone R250. I agree with the concern being balance more than the speed as 18 wheel trucks everywhere exceed the 65mph limit. Not all but alot of them.

Regarding the balance I used a balancer from centramatics that made my truck ride awesome with the 19.5 tire/rims. The tire/rims I have did have a shake after they were mounted and balanced statically that the centramatic balancer corrected. Balance master also makes a similar product but I have never used that brand.

What have you done to balance the 22.5 tires?

RyeThomas

A combo of equal and spin balance. But I still have a little shimmy and shake at some speeds. I am also considering centeramics or something like it to throw into the mix.

JP-4.5

The one thing I did not like about the centramatics was how tight they fit on the front rims on my truck. I used Rickson 19.5" rims and there is not much room between rim and front caliper. The centramatics just barely touch the rim. if the centramatic had a little larger diameter they would have fit great. I am sure this is because centramatic designs there balancer for the truck. They have no idea as to what style/type rim a user may go with.

You may have better options because of the adapters you need for the 10 bolts. You can probably get a 10 bolt balancer and will not need to worry about caliper clearance.

I was going to go with powder, beads or even anti-freeze in the tire but rather not have anything in there that may freeze in the Northeast weather. The anti-freeze I had read several users that swear by it. I thought it just sounded like the wrong thing to do.

Good luck...

ryfrat

What size tires are you running

RyeThomas

The truck is at home so I cant walk out and check but they are Sumitomos and I believe they are 255/70/R22.5 which equals about 37".

ryfrat

thinking about adding some 22.5 to mine.would your truck be to high to tow a fifth wheel camper?

RyeThomas

No idea about the 5th wheel dont have one.

ryfrat

what size lift does it to get those tires to fit

JD Dearden

Dont think you need any lift, these tires and rims lift your truck about two inches i also have a 4'' suspension lift and i do pull a gooseneck, it really just depends on the trailer.

solostyle1

the ones i had didnt shake or vibrate at all. I used the sand weights on both my sets of tires and they worked perfect. The tire i ran both times were the DoubleCoin RLB900.

pupeperson

Regarding the automatic balancers discussed above, I couldn't get the Centramatics to work on the front axle. They just wouldn't fit -- caliper interference. Centramatics on the back fit just fine. Ended up with a pair of balance masters on the front that work very well w/ my 265-70R19.5 Hankook DH01's (34.5" diameter).