Does deeper axle gearing HELP or HURT the transmission?

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Kern Dog

Kern Dog

Build your car to handle.
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I've wondered about this but just now remembered to ask it
Let's say your 3500 lb car has a 360 that runs pretty strong and you have a well built 727.
Axle gearing of 2.76 VS 4.10.
Wide open throttle acceleration, time after time.....which gear would lead to an earlier failure of the transmission?
Just my bonehead logic here but I think that the tall 2.76 gear would place more stress on the transmission because there is less leverage to move the car.
Opinions?

Mopar Mitch 1.jpg
 
You are correct. Because the numerically lower gear is harder for the drive train to turn. The numerically higher (lower ratio) gear is like a longer handle on a breaker bar turning a bolt. You have more leverage verses a short handle.
 
RustyRatRod said:
You are correct. Because the numerically lower gear is harder for the drive train to turn. The numerically higher (lower ratio) gear is like a longer handle on a breaker bar turning a bolt. You have more leverage verses a short handle.
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Makes sense. I agree
 
Kern Dog said:
Wide open throttle acceleration, time after time.....which gear would lead to an earlier failure of the transmission?
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That depends I think on if the tires spin or don't, cuz while the tires are spinning, there is not a lot of torque transmission going on.
But;
the 4.10s will wear the trans out sooner cuz she is spinning more revolutions per unit of time or distance. I mean like planetaries,bushings,slip-rings,thrust washers and such.
 
go from 2.76's to 4.10's and you'll think you put a shift kit in the VB
 
318willrun said:
go from 2.76's to 4.10's and you'll think you put a shift kit in the VB
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Shift mine at 6500 and wait for the possible explosion of parts somewhere in the drivetrain. lol
The blocker rod in the servo adds to the excitement
 
IMO, the only way a 4.10 will be more stressful than a 2.94 is from sheer leverage and more ability to "snatch" things apart. There's always a weak link no matter what you do. When you put say a 4.10 in where a 2.94 was, you're not eliminating the weak link, you're changing WHERE it is.
 
i can't see much of a difference , the torque of the engine is the same no matter what gear is in it .
 
I ask this in part because I am contemplating a change in gearing for my Ram 1500.
I'm going to replace the engine since the original one has 360,000 miles on it and is starting to leak. I want to step it up a bit but keep it emission legal. It has 3.55s now but since even the trucks with 20" wheels got a 3.92, the SRT-10 trucks had a 4.10. They had 22" wheels. I have 22" SRT-10 style wheels on this truck.

Ram A 5 (2).jpg


I think the gear change will pep it up a bit.
 
jimjimjimmy said:
i can't see much of a difference , the torque of the engine is the same no matter what gear is in it .
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That's right, but the different gear can have an effect elsewhere. It's like using a 2 foot long ratchet in the place of a 6 inch long ratchet. YOU are still the same engine, but you can break the **** out of something with a 2 foot long ratchet.
 
jimjimjimmy said:
i can't see much of a difference , the torque of the engine is the same no matter what gear is in it .
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The engine torque needed to move the vehicle is significantly reduced by the gear reduction, the truck weighs the same no matter what, but the load applied to the engine&drivetrain is much less. AJ is correct about standard service-wear, but unless You're only "Aunt Tilley" driving, the reduced loading will drop the wear/rpm....
 
The only problem is most of Us will be inspired to enjoy the new pep & keep Our feet buried in the carpet more often,...so there's that,..lol!
 
AJ/FormS said:
That depends I think on if the tires spin or don't, cuz while the tires are spinning, there is not a lot of torque transmission going on.
But;
the 4.10s will wear the trans out sooner cuz she is spinning more revolutions per unit of time or distance. I mean like planetaries,bushings,slip-rings,thrust washers and such.
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But,....the trans will spend much less time with faster moving gear reduction parts engaged, & get to 1:1/OD operation much sooner....
 
I would think the deeper gears would help in around town stop-n-go driving, easier to get the weight rolling.
But, lots of highway miles.....i think thirty percent more rpm, constantly, would mean thirty percent more wear.
But then, i dont know richard .
I DO know my trans temp gauge says my trans gets a lot hotter (still plenty cool though) in around town driving in traffic, than it does on the highway, roughly 50°.
 
The real answer here, like everything else is, "it depends".
 
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