Alternative gearing available for SM65?

[Christian Nelson]

I know a lot of transmissions have alternative gears people can buy, for close ratio, wide ratio, etc..

Is there anything that would even bring the 1st, and 2nd more into the a usable 4 speed for these?

I find them a lot more readily than true 4speeds, and 5 speeds seem to come at a premium.

I have found rumors about a close ratio alternative gearing for them, but no real sources..

Otherwise, I'll hunt for a 4500, but I'd really like just a 4speed with all 4 useable gears, spaced out properly, and just run higher axle gears if need be.

 

[MikeB]

Doesn't look like there are any aftermarket gear sets for the SM465. What is your axle ratio? If it's 3.08 or numerically higher, you might consider going to a 2.56. Doing that would make that 6.55:1 first gear more usable. As a side benefit, you'd end up with low highway revs in 4th gear. Taller tires would help a little, too.

You could always spend big bucks on an aftermarket Muncie, with the M22Z gearset, which has a 2.98:1 first gear. But then you have issues with fitting a shifter, and possibly a different crossmember. And for the price, you might as well get a 5-speed. Just make sure it can handle your engine's torque. For example, I think even the World Class version of the Borg-Warner T-5 was rated at only 265 lb/ft torque.

 

[Christian Nelson]

Bringing this one back.

I just got a new to me truck, with an SM465.

Guy told me there's companies that make LOWER gearsets for these, for the truck pull guys.

I can't be the only person who wants a useable 1st gear for this tranny.

WHat are the limitations to the design, for why one would have difficulty finding such?

With a regular spread out ratio 4 speed, one could go with a higher differential gear, for better gas mileage, and still have enough to pull decently in 1st.

Any new info?

Do'nt really wanna do an NV 4500..

I have 4.10 gears, thinking I'll swap to 3.73, or 3.4-something.

But, I wonder if I could get away with the 2.- something, with 33" tires, and torque-y 400 small block..

I'll be posting pics soon..