Hello,

This is my first post; I’ll try not to embarrass myself. I just purchased a ’01 F-350 C/C with V10 and 3.73 rear and only 12K miles on the odometer. Several posts report that I should be running around 70 MPH at 2000 RPM. I’m closer to 63 MPH at 2000 RPM. From my read, it sounds like my lock-up clutch never engages (or someone slipped in a 4.30 rear-end). I talked with the local Ford Dealership’s service department and was told to do the following: disconnect my battery for 20 minutes to allow the computer to reset. According to the mechanic, the computer is able to monitor and react to a given driver’s driving habits. My other option is to take it in and spend $75 to have them run some diagnostic checks. The vehicle is still under warranty so if they find a problem it’s covered by the warranty. If no problem then I pay. I figure before I lobotomize my computer I’d see if anyone else has an opinion one way or the other on this.

Thanks, KJ

 

kimpojim, Don't worry about "lobotomizing" your computer. Resetting your vehicles adaptive calibration is something that should be done from time to time anyway and can take care of many little quirks.

A perfect example is my supercharged Cobra. If I spend a few weeks driving normally and then try to drive it like a little old lady it freaks out and starts running very erraticly <sp?>. The only way to correct this is to drive my normal style for a week or disconnect the battery. My point is, newer OBDII vehicles learn the driver's habits and adapt. Just like the mechanic told you.

Here is a tip to make sure you completely drain the ECM of power. First disconnect the battery (remove negative). Once the battery is disconnected, turn the key to the "start" position for a moment then back to "run". This forces the ECM to purge any stored electricity. With this method you shouldn't need to wait 20 minutes, but waiting won't hurt.

Once you go through this cycle your ECM will need to relearn everything including idle. After reconnecting the battery start the truck and let it idle for 5 minutes (do not give any pedal while starting or running). Make sure the AC/Heater controls are turned completely OFF during this time. After 5 minutes of idling, turn on your AC and let it idle for another 15 minutes. Again, no pedal feed. You may notice the AC compressor won't kick on for a few minutes once you turn it on after the battery was disconnected. This is completely normal.

Geez, I dodn't mean to be that long winded. I hope a power cycle fixes your problem! Good luck!

 

Mudder,

Thanks for the reply. I'm filled with a bit more confidence now. I'll give it a try and let you know if this fixed my suspected torque converter clutch problem.

vr/kj

 

If the torque converter doesn't lock the PCM will store an error code and the OD light will flash. If the OD light works and wasn't flashing the torque converter clutch was locking normally.

 

Good point Mark. I don't know if it's a foolproof one though. I've pulled as many as 5 different codes out of an OBDII vehicle that never gave a CEL. Granted some of these codes hadn't been tripped three times yet but others had been and never gave a CEL. Go figure..... These things seem to have a mind of their own sometimes.

But yes, I have a hard time believing that if there was a reoccurring problem like a non-functioning lock-up that a light wouldn't be tripped.

On a side note.... I've seen several of your posts Mark and am guessing you're a Ford trans specialist or something along those lines? Any truth to that?

 

hmmm, if Mark's right and the TCC is working as advertised then something else keeps my RPMs lower than expected with a 3.73 rear gear. I've checked the codes on the door jamb and it reads D1 (limited slip 3.73). I've checked the front axle numbers and it's a 611071-1 or Dana 50, 3.73. It's a bit more interesting on the rear axle. No plate or inscribed numbers. There is a paper tag wrapped around the axle (long side) with the numbers/letter "141H." I've also found "AN01" on the back left of the differential and "0204" on the right rear. All very entertaining considering I live in WA where if it's not raining then it's pouring.

vr/kj

 

I said the overdrive cancel light, not the CEL. The CEL has a different protocol for illuminating. The OD light will flash the first time the PCM sees a problem.

Quote:

On a side note.... I've seen several of your posts Mark and am guessing you're a Ford trans specialist or something along those lines? Any truth to that?

Something like that. It's AMAZING what one can learn by clicking on the "profile" link on the bottom of every post. Some people fill in more than others, though. All I learned from ours is that you'e in Boise. I put more in there...

 

Appreciate the comments!

Well, I got a buddy to watch the drive shaft while I backed up. He counted 3 and ¾ turns of the drive shaft for one revolution of the tire. Guess this means I have a 3.73 rear end. Still at a loss why my speed at 2000 RPM is about 7 miles slower than others with the same set-up. Oh, and I do have stock tires, 265/75R/16s.

Vr/kj

 

Easy check on TC lock while running in 4th on the flat: rest your left foot on the brake just enough to turn the brake lights on. The TC should unlock and you will see a RPM gain on a couple hundred. Foot off the brake, and you should lock again and see the RPM drop.

 

Bill, thanks. I'll give it a try.

 

Bill_s, again thanks. I did get a several 100 RPM increase after a light tap on the brakes and then a decrease when the TCC re-engaged. This is a great forum. Next mission, how to get more power for under $1500. Me thinks banks headers, gibson catback, TB spacer and maybe an FIPK. OK, close to $1500.

kj: