My F250 has the 6.9 and a C6 auto. Lately the trans has been doing hard shifts from 1st to 2nd and I am contemplating doing a rebuild on it and an wondering if anyone has a ballpark on the cost of the job?

 

Ive always been told $1200+ on transmissions. The C6 is one of the cheapest usually.

 

i paid $500 4 years ago to have a C-6 completely re-manufactured with all new internals.
hard shifts are usually a sign of low vacuum.

 

It seems to shift better after it gets warmer. I've checked the vacuum and the lines seem okay.

 

my last one was 800 bucks woth upgrades one or two years a go, depending on what you use the truck for you'll want to get the right tc.

 

I'd honestly check your vacuum pump output, and then VVC port on your IP, and make sure you're getting good vacuum to the transmission. Hard shifting to me doesn't spell bad transmission, slipping in gear or puking overheated fluid does. Hard shifting is more like bad vacuum so the trans doesn't hold on to 1st while it shifts into 2nd. It just lets go of 1st completely and grabs 2nd, which is where the hard shift comes from.

 

You are in anchorage, take it to Top Jimmy, if they are still there, hard shifts does not mean its bad, and they did real good work on a friends truck when I was up there a few years back.

 

Does anyone have a schematic that lays out the vacuum lines and where they run? Also where is the VVT on the IP? I've been meaning to check my pump out anyway and maybe turn the screw up a little bit. I'm sure the trans is still good I just haven't experienced this hard shift before.

 

you need to put a vacuum gauge on a vacuum fitting and see how much it is pulling.

then step on the brakes a few times and see how long it takes to recover.
anything under 17 inches vacuum and the trans will not shift properly, but over 19 inches is preferred.
there is no sense messing with the VRV on the pump if you have low vacuum.

 

If your vacuum is good then check the modulator. Cheap and easy.

Also, one of the bands on the C6 is externally adjustable. Either the 1st/Rev or the 2ond/3rd. Forget which at this time.