[Russell]

They are not an easy transmission to overhaul, and plenty of shops simply are not equipped to do so. The last one I had "overhauled" involved me purchasing a new one from the transmission shop to the tune of $2000. After turning in my old core they re-paid me $800, so it wound up being a $1200 replacement. Keep in mind that is in Canadian dollars, and you can usually add a good 20 - 30% on anything that I buy / have done up here vs the cost in the USA, not to mention the difference in currency values.

An NV4500 would cost only a few hundred bucks more, but it isn't the end-all to all O/D manual transmissions. It has plenty of weaknesses (particularly with the 5th gear), and again, it drives like a mid 80's SM465 with an O/D gear tacked on to the top. NV3500 drives much nicer, and is a true 5 speed transmission (NV4500 is more of a 4 speed)

I suppose it all boils down to how you drive the truck, and what your purposes are. If you have a daily driver that doesn't haul much more than passengers around, and isn't powered by a overly powerful engine, an NV3500 is plenty adequate, despite it's reputation. NV4500 is does great in trucks that are abused offroad, used to haul heavy loads, or is powered by something that'll just shatter the lighter transmission.