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I need to know if anyone has the correct # of teeth for a truck with 235/85R16's and 3.55's.

It had a 31 in it, and I called Rickson to get the correct one, and they sent a 30...I thought more teeth would speed it up.

I was right, now at 70 (speedo) my GPS has me running ~67mph.

Do I need a 32, or which one??

Thanks,
Chris

MDKram

Chris, the 30 tooth gear is the best one I have found with the 235/85s. I am roughly 1% out with the 30 tooth gear (using Meridian Gold GPS). it appears as though you may have to try a 29 tooth. I run the BFG A/T ko at 70 psi.
Marc

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With the 30 it was about 3% off. Not really a big deal, but I like having the odometer correct for mileage and other stuff.

I do some hauling where I need good mileage records.

Thanks,
Chris

MDKram

Chris, I was half asleep last night. A 29 tooth would speed things up more so disregard that comment. What air pressure are you running in your tires?

I assume your speedo read slow when you had the 31 tooth gear in? It may be a better choice for you if you were only 3% out. Now, it appears you are about 4.5% out as you have probably calculated. Sorry I can't offer more help.

Marc

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75psi rear, 70 Front, I think.

Haven't checked it lately, but it's always right on.

Thanks Again, I'll order a 29 Monday,
Chris

Bram

Just curious, did the 29 work?
The reason I ask is I have the same size tires and need to change my gear also.