Tires for K3500

[Duramax Dually]

Sorry to bring a new thread back about this but I did a search and read a lot of threads and none seem to be conclusive to the answer I am looking for.


What is the largest tire you can run and remain safe? I am not worried about brand wars however I would like to know if one over the other has a larger sidewall 'bubble' and has a larger chance of rubbing in the back. I am not adding spacers so that is out. It appears that 235/85/16 seems to be the size. I am not towing my 11K lb trailer anymore but just a boat and small utility trailers with 3-4k of weight.


What is the overall diameter difference of the 235/85 vs the 215/75?


As always appreciate the feedback. If you have pics of your truck I would like to see.


Thanks

[Diesel Dad]

I have both Cooper Discoverer A/Ts and Michelin XPS Ribs in LT215 85/16 LRE. Not sure I would go bigger with the stock rims.


While a lighter load will cause less bulging, you would also want to run with lower tire pressure for a better ride (perhaps 40 to 50 lbs.) and that would cause more bulge.

[White Duramax]

I would go with 235/85R16's they will fit fine on stock rims and are a little bit taller.

[Super Diesel]

The 215 85/16 is about 30.38 inches tall (depending on brand). The 235 85/16 are about 31.73 inches tall (depending on brand). All in all, you will gain only about .675 of an inch in hight. However the are about .787 wider each. You really should put at least a 1/4 inch spacer form JC Whitney or Jegs between the rims. They are only about $8 each. I run 255 85/16 with a 1 inch spacer between mine, and they look pritty good. I need the exrta ground clearance they provide. Sorry, don't have any pics to up load yet. Super Diesel

[Michigana_Joe]

Originally Posted by Super Diesel

The 215 85/16 is about 30.38 inches tall (depending on brand). The 235 85/16 are about 31.73 inches tall (depending on brand). All in all, you will gain only about .675 of an inch in hight. However the are about .787 wider each. You really should put at least a 1/4 inch spacer form JC Whitney or Jegs between the rims. They are only about $8 each. I run 255 85/16 with a 1 inch spacer between mine, and they look pritty good. I need the exrta ground clearance they provide. Sorry, don't have any pics to up load yet. Super Diesel

On stock rims? What kind of 1" spacer?


I recall a guy on thedieselpage (TexasRedWagon I believe) running 255/85's without a spacer on Neeper aftermarket wheels, but I imagine they have more offset than stock.

[Heartbeat Hauler]

The following was a response to my question from Southwest Wheel in regards to wheels and spacers.....


This is a common question and the answer is one that most do not want to hear. When Chevrolet redesigned the new 16"x6.5" dual wheel for 2001-current trucks, I had the privilege of working with a GM engineer and Alcoa. I was told they designed the wheel to run no tire larger than an LT215. Their goal was to create less bulge on the tire. They did this by designing a 16"x6.5" rim width, basically .5" wider than a traditional dual wheel. Most would think you could run a wider tire, but they then pushed in the offset and changed the curvature of the wheel. Now to answer your question on the spacer, this is a bad idea. The modern dual wheel is a hub piloted system, meaning the entire weight of the vehicle rest on the center bore. The purpose of the swiveling flange nut is to create a large amount of pressure on the two flat faced wheels against the hub. This allows all the pressure of the wheel to return to the center bore. If you allow an object between the dual wheels you increase the chance dramatically of vibration or stud breakage and you will automatically void your warranty. If you run the larger tire without the use of a spacer, the tires will rub together creating heat and increase the chance of "blow outs". So for the purpose of this discussion by increasing the size of tire you reduce the overall performance and weight carrying capacity of the truck using a 16" wheel. Modern steel wheel manufacturers can not justify a cost to produce a wheel with a different offset. One reason is the ability to produce enough volume for the tooling and the second is the liability of re-engineering the wheel. Your alternative is to move away from the 16" wheel, but finding a wheel with the correct center bore and offsets will be hard to do. Alcoa Wheels will be producing a 19.5" version wheel that will directly fit on the new Chevy/GM trucks in the coming year.


JP

[Texas Red Wagon]

Originally Posted by Michigana_Joe

I recall a guy on thedieselpage (TexasRedWagon I believe) running 255/85's without a spacer on Neeper aftermarket wheels, but I imagine they have more offset than stock.

That is correct
Scott

[Super Diesel]

I have the Neepers as well, But I also carry a slide in camper. With out the spacers, the wheels rub together severly. I have had no problems in 50,000 mi. so far. My camper weight is 4500 alone. However the inside rims are stock stamped steel. The Neepers have only slightly more offset then the stockers. I have the exact same truck except for the exhaust (Banks), and mine is white. Even the PPE stuff (good choice). I also installed air bags and the Ranco 9000 shocks all the way around so I could adjust the ride. Super Diesel

[Duramax Dually]

I am quite concerned about running spacers. I know many people are using them but it just does not seem like good practice(Same with adaptors) Mechanically speaking, by spacing out the outer wheel even a 1/4 of an inch you put a tremendous load on the stud as the tire/wheel assy moves away from the hub. I gave up on the 19.5 wheels as that was my original plan. But after hearing about some of the crack pots sueing people that have aftermarket wheels and getting in wrecks I thought staying with stock configured wheels is safest. (More on that at the bottom of my post)


I have the Alcoa Magnum wheels(stock OEM specifications) sitting in my garage. I am just trying to decide what tires to put on them. I am done with the big 11Klb trailer towing but will tow a boat from time to time, tow around utility trailers and carry my quad runner(600lbs). I just do not want to buy the tires to have them touch when I hook up something. so I am looking for input from people running the 235/85 tires with stock wheels or after market with OEM offsets.


Here is something to ponder


Can you believe that people are sueing people that get in wrecks and have aftermarket wheels due to the fact on new cars the taller the tires and taller the wheels it has adverse affects on the ABS system which means you are altering the safety features of the car. As a consumer you could now personally liable. There is case I heard currently going on with a guy that put 20"s on his Denali and hit someone and it was a lot of damage. The auto insurance company does not want to pay out due to the fact the consumer modified the car. This means YOU could have to pay ALL expenses out of YOUR pocket. This could get quite ugly in the coming years. Wait until your insurance company puts out a clause in your policy that says they will only cover you if your car remains as it was delivered from the factory, if you modify they will not cover you...OUCH . Look at the cell phone action coming up with insurance companies...well anyway enough of that......

[Texas Red Wagon]

Super D
What tires you running.
I pull a 22' f/s boat and that's about it.
Scott