I think the warranty claim process gets complicated if you buy a reman unit and have a shop install it... it might be more expensive as well if you factor in the installation cost.
I'm possibly going through the same thing now. What I have learned is to find a shop that has specializes in older transmissions. While the C6 transmission is assumed to be simple, I believe if you want the best outcome it is better left to a shop who has done is many many times before so they get it just right the first time. I have found that small mistakes can be expensive in transmissions.
In my case, the cost of 4x4 C6 rebuild is quoted to be around ~$1700 including removal and installation assuming no hard parts are to be replaced (Except torque converter). New reman units are approx the same price but with removal and installation labor it might be a tad higher. I called another big-box name brand shop that rebuilds new 6 speed, 8 speed transmissions and they were very unclear and clearly not knowledgeable on older transmissions and sure enough they quoted very high ($4500) as they weren't sure what they were dealing with. I don't think you should go with the cheapest quote but sometimes cheap may not mean bad. When it is coupled with good reputation, it might mean... "we know what we are doing".
About Junkyard transmissions, probably best to avoid as the labor to remove and install is the same as a rebuild and I doubt they are tested. Much rather pay labor cost once. Usually they are best used as a base for a rebuild.
Vivek
- BB 2WD - 1984 F350 RWD 460/C6
- 1978 Bronco with a 460 from an 86 Bullnose/C6