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Anybody regret going with 37s over 35s?

I went from 35’s to 37’s on my ‘22 Hemi, 3.73’s. But I went with a 37X11.50, the skinnier tire helps with plowing and no rubbing, 2” level, 5100 shocks & Thuren sway bar. For ME, my fuel mileage and my trans temp did not change from 35’s,the truck rides nicer with the taller sidewall & I don’t really notice much difference in acceleration .
 

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I went from 35’s to 37’s on my ‘22 Hemi, 3.73’s. But I went with a 37X11.50, the skinnier tire helps with plowing and no rubbing, 2” level, 5100 shocks & Thuren sway bar. For ME, my fuel mileage and my trans temp did not change from 35’s,the truck rides nicer with the taller sidewall & I don’t really notice much difference in acceleration .
Usually I think 11.50s look too skinny, but it looks good on your truck with the stock wheels!
 
I think the only people with issues are those with the 68RFE. lol. So glad that transmission has been discontinued.

And theirs no need to re gear with the ZF PowerLine.
 
We hope the ZF ends up being better, but it hasn’t been out long. Regardless of transmission though, if the gearing isn’t changed for the different sized tires there is more leverage and a lot of it placed on the transmission.
 
We hope the ZF ends up being better, but it hasn’t been out long. Regardless of transmission though, if the gearing isn’t changed for the different sized tires there is more leverage and a lot of it placed on the transmission.
That exact same transmission is and has been used in much larger applications than the Ram 6.7

Nobody with a ZF and 37’s have said they felt the need to gear. In fact, the ZF has a much more aggressive gear ratio than 4.10.

First gear of a 68RFE is 3.28
First gear of a ZF PowerLine is 4.89

The drivetrain with the ZF is plenty happy with 37” tires.

Stress on a transmission isn’t just about tire size. It’s about converter slip, heat, shocks load, sustained towing load, and tuning. The ZF isn’t going to suddenly operate on the edge of failure with 37 inch tires.

With how close the gear ratios of the ZF are, 37’s keep the transmission in its powerband instead of lugging. Lugging with 37s and the 68RFE (on top of it being a chit transmission) is what kills the drivetrain. High load at low RPM is where stuff fail.
 
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That exact same transmission is and has been used in much larger applications than the Ram 6.7

Nobody with a ZF and 37’s have said they felt the need to gear. In fact, the ZF has a much more aggressive gear ratio than 4.10.

First gear of a 68RFE is 3.28
First gear of a ZF PowerLine is 4.89

The drivetrain with the ZF is plenty happy with 37” tires.

Stress on a transmission isn’t just about tire size. It’s about converter slip, heat, shocks load, sustained towing load, and tuning. The ZF isn’t going to suddenly operate on the edge of failure with 37 inch tires.

With how close the gear ratios of the ZF are, 37’s keep the transmission in its powerband instead of lugging. Lugging with 37s and the 68RFE (on top of it being a chit transmission) is what kills the drivetrain. High load at low RPM is where stuff fail.

I understand what you are saying there. All I am saying is the entire drivetrain including ratio’s was designed with the intention of a 285/60r20 on the wheels. Not a 37x12.50. Which will wear parts out eventually, how long that lasts depends on many factors and is completely subjective to case by case scenario.
 
No issues no regrets.
 

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I love my 37's, can't wait to throw them back on for the summer. I do swap down to 11.5 x 35's in the winter for better traction and to take some stress off the trans, also I think i'd get some rubbing with the weight of the plow if i left the 37's on.

Stock ride height, stock 68RFE, 3.73's, and I've gotten 23.5mpg manually calculated on my drive to florida. It tows my 9500lb toy hauler through the mountains of PA & WV just fine, trans temps rarely exceed 175. I do however drive pretty conservatively, I understand it's a truck not a racecar, so I save the hot rodding for my beater car.

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