I've got an 88 f-150 that had a mozda 5-speed transmission in it that went out so I swapped in a c-6 from an 83 f-150. I'm having trouble now with the c-6. The truck has reverse but not much in the way of drive. Every once in a while it'll go forward, but not to well. If I rev the engine up the slightest bit it slips really bad and if I let out of it the tranny will renegage sometimes and sometimes it'll just set there. I suspect the transmission is toast, but I was wondering if there is something I can try to adjust before I go and remove the transmission and go in search of another junk yard c-6.
Thanks for any advice.

 

hey Scott,

I suppose you have check the tranny fluid (ATF)?
If yes, with running or not running engine?
...and what about the tranny filter, do you changed it?

I know, it's a very dump question..., but just an Idea.

Jens

 

I changed the filter and fluid when I swapped the tranny. I'm starting to winder if I dont have enough cooler for the fluid. I just went to summit and bought a transmission cooler that was pretty big and plumbed it up to the lines from the transmission. I dont think I'd need a radiator from an auto truck or do I?
I might even look into the possability of rebuilding this transmission if I can find a manual online that shows how to do it. I tried searchig for a c-6 rebuild manual online, but all i could find was links for books that I'd have to purchase. If someone knows where I can locate a manual online I'd appreciate it.

 

scott460,

It could be a lot of things, but it sounds to me like a fluid level problem (that's the first thing I would check).

Make sure to check the transmission fluid level with the motor running, in Park or Neutral on a level surface. Add fluid slowly (careful not to spill on the hot engine!) until you hit the fill mark. Then get in the car and move the selector to every possible position (Neutral, Drive, 2, 1) and leave it there for a few seconds to make sure you have all the air out of all the circuits. Check the level again.

Be very careful not to overfill.

If it's still giving you troble after that, I'd have it checked my a transmission shop to make sure the pump isn't dead.

Also, make sure the shifter is properly adjusted and not holding between two spots. Just make sure the detent lever is acutally in "drive" when you select "drive". This is another common mistake.

One of *the* most common mistakes that people make with automatic transmissions is not getting the Torque Converter properly engaged with the pump drive when they bolt the transmission assembly together to the engine. The TC usually has slots or grooves that engage with the pump drive...if this not engaged when you bolt the transmission up, and fire the engine...you ruin the pump and need to replace it (read: take it all apart again).

Anyways, go for the fluid check first...make sure all the connections are correct, then make sure the detent lever is right. After that you should probably have a certified mechanic have a crack at it.

Dan Martin
86 F350

 

Come on, I am all for what you are trying to do, (rebuild it yourself), but you can buy the rebuild kit, any special tools you need, AND THE BOOK, and still be money ahead.