With 35" Tires what do you guys do about

[hammersley]

1. Changing the Speedo Error - does the Smarty Jr do this?



AND



2. Spare Tire - the 20" 35 obviously won't fit under the back - how much harm - if any - does running with the factory spare do????? I mean I've seen cars with the cheap spares which are a different size.....

 

[MechanicMike]

Depending on the year of your truck, you can have the dealer flash the computer. Thats what I did on my 04. The smarty will do it too but not sure about the newer trucks though. As for the spare, I still run the original spare under there with my 35's. I keep a tire plug kit and a small compressor in the truck with me just in case. In an emergency ( blow out on the highway) I would install the spare temporarily but wouldn't drive any farther than I had to with it. Hope this helps.



Mike

 

[hammersley]

Depending on the year of your truck, you can have the dealer flash the computer. Thats what I did on my 04. The smarty will do it too but not sure about the newer trucks though. As for the spare, I still run the original spare under there with my 35's. I keep a tire plug kit and a small compressor in the truck with me just in case. In an emergency ( blow out on the highway) I would install the spare temporarily but wouldn't drive any farther than I had to with it. Hope this helps.



Mike

Thanks - that's what I thought... ... .

 

[S.Morris]

Smarty jr will set tire size.

If you need to run spare put it on front.

Rear LS will not take kindly... ... to different sizes.

Even air pressure needs to be kept even so overall

Dia remains same on both sides.

 

[BDaugherty]

I do the same. I plan to just plug/patch a tire and keep on going. The factory spare is my backup plan. I would have to run it in the front due to the limited slip in the rear.

 

[Jeepr]

Others already covered you can't have two different sizes on back. But, I have a 35" spare and it fits in the tire holder. I have 17" wheels, but it shouldn't matter.



Up through and including 2005 model year, the dealer can go into the computer and put in your tire size to adjust the speedo. They have a menu of "stock" sized tires and an "other" setting. When they go into the "other" setting they can input the revolutions per mile of the new tires. So, you will need to know that, if you don't know, usually the tire manufacturer's website or tirerack.com have it.



2006+ can only input tire sizes from the factory (yet ANOTHER reason I'm glad I got a leftover 2005! )

 

[DBentley]

I just add 10% in my head to the speedo reading for the summer months that i run the 35s.
Seems to be the best way to me.
Also i add 10% to miles traveled at each fillup to hand calc M. P. G.

 

[MickeyMiller]

I'm with Jeepr, I fit a 35" spare in the stock carrier without too much trouble. I now run with (2) 35" spares mounted in the bed!

 

[TAbbott]

I have a fulll size 265/70R19. 5 spare tire that measures 34. 5" overall diameter. It fits in the underbed spare rack. It's close, but it fits.