Any ideas how much power a nv4500 can handle, and does these elevated power level drastically reduce the service life of these?

Dave

 

So far I have seen more U joints and driveshafts, frames etc. dying before a good NV4500 does........

 

The 4500 can handle lots of power.
Problem is parts for them are getting harder and harder to come by.

 

Whats the worse thing for them? Lugging them right?

 

My original trans lasted 160k, I had added the plate at about 98k. Since then I have had only two transmissions go over 100k, and have had major failures with as little as 7k. Average 100k for a rebuild. They were designed for about 450 lbs of TQ, my 97 engine stock was rated at 440 at the flywheel. After I was able to dyno 611 at the wheels which was, I'm guessing, 700+ at the flywheel, longetivity decreased dramatically. A short answer to "does these elevated power level drastically reduce the service life of these?" is YES!

 

What did you break, and were you towing a lot with it?

 

Yes I tow a lot, like 70 to 75% of the miles, sometimes pretty heavy. Usually the gears on the countershaft go. If I press on in 4th gear, and I have a couple times, every gear in there fails. I believe, but do not know for sure, that towing in 5th wears the countershaft bearings bad enough to permit the gears to impact other stationary gears, and that gets the ball rolling. At least that is what three of my total failures sounded like. A lot of clicking, growing louder in intensity until all h*** broke loose.