1987 Silverado 4x4 700r4 shifting into 4th to soon?

[Mike Phillips]

1987 Silverado 4x4 700r4 shifting into 4th to soon?

About 3-4 months ago I installed a rebuilt 700r4 transmission into my Chevy and it's worked perfect till just recently where now it's shifting into 4th gear too soon.  It will shift into 4th around 40 mph.

Before it would shift into 4th around 50 or 60 mph.

Anyone have any idea what could cause this change in operation?  I have changed nothing else on the truck and driven it sanely.

[Captkaos]

Recheck your TV cable adjustment.

[Mike Phillips]

Recheck your TV cable adjustment.

Thanks for the suggestion.  That's the first thing I checked and just to troubleshoot I adjusted it to shift later and no effect.

I took the dash apart to try to fix the gauges, (no luck there), so I'm wondering what drives the electrical current for the lock-up?

[Captkaos]

There is a solenoid that controls the lockup on the trans.

[Mike Phillips]

There is a solenoid that controls the lockup on the trans.

Thanks Chris,

My transmission guy Dana told me this also, told me to drop the pan and look for metal particles.  Says their could be metal particles intrrfering with the solenoid.