Hi all, I need to know what transmission is in my truck, (see sig) I think it is a C-6.

The code is (K) on the door tag.

The problem is when I shift it into any forward gear it won’t engage tell I rev the engine then it engages and all is fine, it will do this every time I shift from park or reverse to drive.

The fluid is clean and full, it doesn’t slip and the shifts are good and firm. Once it is in gear it is fine, but I don’t like having to rev the motor just to get it in gear.

Also can some one help me decipher the door tag codes? They are

Body: DKM
Trans: K
Axle: C5
Spring: 73F

Thank you for your time.

Tom Cat

on edit: What is the HP and TQ on my truck

 

Hey there Tom Cat! Welcome to FTE! I can assist a bit... I don't have the codes yet for you, but I'm sure that before I find out, the answer will already be replied.
It does sound like your tranny is going to need a re-build though..
Slipping is the term you used above and when you engauge drive, you are raising the rpms to help engage the clutch plates, so yes, there is slipping. It doesn't matter how much fluid you have in the tranny. Once the damage is done, you can't reverse it.

Has any work been performed on the tranny before you noticed the problem? I was just wondering... If it had, then whomever serviced it, may have made an adjustment, where none was needed, or may have installed a part in the wrong direction. Something that would make it seem like you are actully in drive looking at the gear shift indicator, but in neutral momentarily, and the shifter handle finally drops into the proper position when you apply the gas pedal, which in turn, does move the motor and tranny (twisting) a bit. For I.D. purposes, you'll have to get the number off the tag on the tranny.
For that matter, those codes may have been on the door since 1988, but may have been changed out by a previous owner. Or the door could actually be from another truck if it had been replaced. You'll have to do some searching for the numbers on the parts you want to I.D.
HP= about 180 at the flywheel/Torque= about 260 ft lbs at the flywheel.

Have the tranny checked over though. Cal the BBB to check on the Good Guys out there!


A short story: I used to have a Buick/321 V-6/350th. I lost forward momentum on an x-way. Had tons of engine. Just before I shut the thing down, a small chunk of metal came through the tranny hump, hit under the dash and landed on the floor. I had lost my torque converter and in the process, the aluminum flywheel shattered. Shut it off, looked at the fine mess scattered all under and called a tow truck. That afternoon, I bought a 76' Maverick! Talk with you guys later....

 

You probably have a C6. What does the shift indicator say? It's either a C6 or an AOD overdrive transmission.

Double check the vacuum line going to the modulator. If it is still attached, pull it to see if fluid comes out. If it does then the modulator is bad. If not, then you really should take in to have it inspected. It possibly could just need a band adjustment since the fluid is clean and not burnt smelling.

The only codes I know are the Axle code - C5 = 4.10 W/ Limited Slip.

 

K is the C6.

 

Thank you all for the replies, now that I know for shire I have a C6 I will pick up a new filter and pan gasket at Napa tomorrow.

The funny part is like I said, once I get it to engage drive it goes like crazy, shifts good and don’t slip a bit. I hope a filter and fluid change will cure it.

90f150moneypit

How do you like the 204/214 cam? Is that duration at .050 lift? Before winter I plan on replacing my timing chain (with a double roller) and valve cover gaskets. If I go that far in the engine I might install a torque cam with specs close to yours (should work good with the 4.11’s and no OD).

Now if I just can just get the rest of the door codes figured out it would make me a happy person.

Thank you for your time.

Tom Cat

 

I hadn't noticed the codes in your first post; I'm looking them up...
My lists say DKM is knit & vinyl bench in a super cab fleetside in either teal or chestnut.
C5 is a Sterling 10.25" 4.10 possibly limited slip.
I can't decode "73" (usage codes), but the F decodes to part number E0TA-5310-FC which should be a 5-leaf pack rated at 2700lb at the pad and 6100lb at the ground.

You can look up door codes at these sites:
https://www.ford-trucks.com/articles/2003/9.php
http://www.fleet.ford.com/truckbbas/...7/c42_46_p.pdf
http://www.broncodata.com/

 

Yes the cam spec's are at .050 lift. I can't truly quantify the results as of yet. I had a lot of problems, related and unrelated.

I had a rattle/knock after warm up I am tracking down. I just verified it isn't the low end. So now I'm waiting for back ordered parts to seal the bottom up.

I have been reading quite a few post's about cheap oil filters causing such a thing and I have always used Napa filters, so I will try a motorcraft filter. Plus I didn't change the valve springs with the swap. It overheated just before the swap, so I'm thinking the springs tensile strength was reduced. So that is next on my list.

When it was cold, it ran great. Low end responce was less than I wanted but until I get it running right I will not know. Freeway speeds it was great.

It sounds real good though, with the single exhaust without a cat and a glasspack you can hear the seperate exhaust pulses while cruising. (yes, an exhaust system is on the way as well).

 

Don't know if this is the same, but:

Not sure if it was a Ford, but one of the trucks I drove in late 90's had a similar problem. Shop said there was a little check valve that prevented fluid from emptying back into the pan when the engine was stopped or low revs. When the valve got grit in it, the fluid drained down and the tranny didn't "wake up" until a second or 2 after you started accelerating.

FWIW. Rufus

 

Fluid and filter won't help an engagement problem. Most likely the seals in the forward clutch are hard and worn. An OH is in order.