4:88 or 5:29 on 35's towing 1200 trailer? (1 Viewer)

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So would 4:88's and transfer case gears be too much on 35's ? I drive at 75mph for hours to get to my destination.
 

baldilocks

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So would 4:88's and transfer case gears be too much on 35's ? I drive at 75mph for hours to get to my destination.
As you have read, opinions matter. Under drive gears plus 4.88 equals 5.29. That combo will give response but you’ll be running 3,000rpm or above at 75.
 
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So would 4:88's and transfer case gears be too much on 35's ? I drive at 75mph for hours to get to my destination.

So for those that are concerned about RPM with different gear sets in your 3rds you can use this calculator and get an idea where your RPM would be.

stock with under drive = 4.52
4.56 with under drive = 5.016
4.88 with under drive = 5.368

Use the numbers above to plug in for your ratio with under drive, then you can put your personal tire size and switch out MPH to get different RPM.

RPM Calculator
 

cruiserdan

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I have 4.88s in my truck and my wife's truck has 5.29s. We are in identical 315/75/16 tires. Mine is supercharged, hers is not. She loves the 5.29s. They pretty nuch make her truck a 65 to 70 mile an hour ride. Any more than that and it feels like the motor is trying to crawl out through the radiator. :lol:
 

thatcabledude

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I have 4.88s in my truck and my wife's truck has 5.29s. We are in identical 315/75/16 tires. Mine is supercharged, hers is not. She loves the 5.29s. They pretty nuch make her truck a 65 to 70 mile an hour ride. Any more than that and it feels like the motor is trying to crawl out through the radiator. :lol:
 
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From memory the 1FZ go open loop at roughly 3100 rpm so MPG is going to get even worse if you gear yourself into a cruising speed above that.

With 4.88 and 37’s my truck is pretty dead on to the Speedo. 3000rpm is about 80mph. Personally I consider this ideal. I do tow regularly. I do want the low range T-case gears. I have a Wits-End turbo to install to cure the HWY shortcomings.
 
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I have 4.88s in my truck and my wife's truck has 5.29s. We are in identical 315/75/16 tires. Mine is supercharged, hers is not. She loves the 5.29s. They pretty nuch make her truck a 65 to 70 mile an hour ride. Any more than that and it feels like the motor is trying to crawl out through the radiator. :lol:
At what RPM is your wife running at 70mph?
 

cruiserdan

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At what RPM is your wife running at 70mph?

I don't drive it often. If memory serves it's around 3,700 RPM in 3rd (direct) and around 2,900 in OD.
 

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