Does anyone know of a gearbox that can mount after the tranny to give extra overdrive ratios? Mine is topping out too early.

Thanks.

 

Interesting thought, but I do not think this is anything that exists in the real world, or I would be surprised if it did. What you are actually talking about is a transmission with more gears. For example 6L80E instead of 4L60E, to give you 6 versus 4 speeds. And the vehicle has to know how to control it and know about those speeds, and when the shift points are.

 

And it is a lot less expensive than US Gear (out of business now?) and GearVendors. The GearVendors unit is ~$4K. Beside, used might be a possibility.

Thanks for the idea.

 

If your 1993 truck using the 4L60, and not the 4L60E (electronically controlled), then you may have some hope of making a change happen, if you find another non-electronically controlled transmission with more gears. My understanding from reading about a similar transmission swap on newer GMT800 (early 2000's) trucks going from 4 speed to 6 or 8 speed also involved reprogramming of the computers, and a lot of custom work.

 

OBD1 and diesel, so maybe not a big deal. I don't know for sure. Maybe there is an aftermarket controller to take over the duties based on existing settings.

 

That GearVendors solution does look perfect. I had no clue such an item existed. Just so much money to throw at an old truck though... I love my 1996, but not that much...

 

Amen to that, Brother!

 

The upshot of all this was that Eaton directed me to a place in my state at Drive Train Specialist. The guy there was very helpful and suggested the replacement ring and pinion from Yukon for $459. That would give a 3.42 because the 3.73 would not make enough difference. Makes sense to me.

If you're sitting down, I will tell you that they will install it for you with new bearings ($249) plus labor ($800) and extras for ~$1600.

Still that it the cheapest solution, and if you know how to fit this 10.5 inch unit together correctly, you can do it yourself and save a bundle.

I figure the vehicle could still pull the heaviest load at a relatively slow start up speed and accelerate thru the gears by using them thru the RPM range until reaching cruise. Cruise should then save some fuel and engine wear from high RPM.