C6 question

[LumbermanSVO]

I have an '86 F250 4x4 6.9L with a C6. I'm curious if the C6 is working properly.

When I put it in "D" and let off the brake the truck seems somewhat eager to move, it will climb small hill at idle and what not. If I put it in "2" it doesn't seem to want to go anywhere until I give it a fair amount of throttle. If I put it in "1" it seems very eager to move, even more than "D".

If I go from "2" to either "D" or "1" I can feel the truck jump foreward, definatly a BIG difference in easily it will move.

Is this normal for a C6 truck? If not where do I start looking to fix it? Could this be part of my poor fuel mileage?

 

[suv7734]

This is normal operation for the C6. When you put it in "D" it is actually going into first gear the same as when you put it into "1". When you put it into "2" the transmission is actually going into second gear and will not 'pull' as well due to the gear ratio/torque convertor slippage. If the truck is really trying to 'launch' when you put it in gear you may want to check the idle RPM which should be 650 +/-50 RPM.

 

[LumbermanSVO]

Thanks, sounds like its running good.

 

[WD40]

SUV is right, never take off in 2 with any auto transmission. When you do that you have it locked in 2 and the transmission can't do any thing. So also take off in Drive or in Low then shift up to sec then to drive.
A mild shift kit works great in a c-6 for pulling a trailer.