C6 Question
Thread Starter
|
Senior User
Joined: May 2001
Posts: 179
Likes: 0
C6 Question
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?
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?
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
The C6 has the ability to start off in second gear, thats why you feel a difference between D and 1 as opposed to 2, there is more torque in first than second, so you feel the engagement as being more positive in first gear.
It sounds like its operating normally, unless you are noticing some strange shifting, overheating, or other issues with the transmission, I wouldn't worry about it.
As for fuel econommy, well, yes and no. The C6 is a very reliable transmission, but its not a very efficient one, and a stick shift is usually worth a good 2-3mpg over the old C6. But the C6 has no true direct mode, since it is has full time open torque converter.
When I still had a C6 in my 86', I would get anywhere from 13mpg, all the way up to the low 20s once in a while, but consistently, the truck was only good for about 15-16mpg, and thats with 3.08 gears (speeds ranging from 60-75mph and many hills ranging from 2-4%)
Just how poor is your fuel economy?
It sounds like its operating normally, unless you are noticing some strange shifting, overheating, or other issues with the transmission, I wouldn't worry about it.
As for fuel econommy, well, yes and no. The C6 is a very reliable transmission, but its not a very efficient one, and a stick shift is usually worth a good 2-3mpg over the old C6. But the C6 has no true direct mode, since it is has full time open torque converter.
When I still had a C6 in my 86', I would get anywhere from 13mpg, all the way up to the low 20s once in a while, but consistently, the truck was only good for about 15-16mpg, and thats with 3.08 gears (speeds ranging from 60-75mph and many hills ranging from 2-4%)
Just how poor is your fuel economy?
Junior User
Joined: Jul 2005
Posts: 65
Likes: 0
As an old, used to live in Wyoming person. You will find the C6 is one of the best transmisions in snow in town. If you put it in second it never shifts. It doesn't spin the wheels as in first gear, and when you top a snow covered hill you don't have ronaway on the back side of the hill from being in a taller gear. If you are parked in an uphill next to the kurb, just set the hand brake and drive away overpowering the brakes. (Don,t forget to release them after you are moving.) Also don't forget and set the hand brake when you park in the winter or you won't be able to move until May or June.
Thread Starter
|
Senior User
Joined: May 2001
Posts: 179
Likes: 0
Ok, thanks guys. I've never owned an auto before, like sticks much better. I had never spent much time behind the wheel of other auto's so I wasn't sure.
I get between 11 and 11.5 MPG running commercial B99 and all light footed in-city driving.
I get between 11 and 11.5 MPG running commercial B99 and all light footed in-city driving.
Tuned
Joined: Oct 2006
Posts: 375
Likes: 0
From: Beaumont Tx
We have a C6 in the F250 we use for plowing and I have pushed snow drifts taller than the truck in first gear. I don't advise this but when you have idiots plowing the driveways while you run the roads in a condo complex you tend to appreciate a tough transmission. The only thing I would suggest is installing a shift kit and an external stacked-plate cooler. As the other have said the C6 is an almost indestructible unit. Keep the screen clean and the fluid fresh and it can outlast the truck.
