Hi everyone, I've been a long-time lurker but I am in need of help from anybody that may know something.
Car description: I have a 2006 expedition with the 5.4 3v. The truck currently has 143,000 miles. I bought it when it had 126,000 and the transmission was never serviced until I bought it (found the little transmission plug at the bottom of the pan). Since I bought it, I've done the transmission drain fill and filter change twice. Also, I made the mistake of removing the transmission bypass when I replaced the transmission lines (around 140,000) so in the winter I have to warm-up the truck 5 to 10 minutes before driving it otherwise I get a very rough shift and bang when going from first to second gear. I live in Virginia though, so I was under the impression that it didn't get cold enough to damage anything internal (perhaps I'm wrong).
The problem:
1. momentary rumble sound/feeling like I'm going over a pothole or rumble strips. This mainly happens when going above 40 mph and only does it when I've stopped accelerating and tapping the gas lightly to cruise.
2. Loud bang when shifting into drive but much more pronounced when shifting into reverse.
3. The truck will tend to roll forward if I'm backing up my driveway and let go off the gas or similarly roll backwards if I'm stopped on a hilly road.
4. If I'm stopped and lightly press on the gas the truck will rev up fine but will throttle down quickly. This sort of feels like a misfire once I let go of the gas. It almost feels like the VCT's advance timing but then abruptly close, but I've ruled out the VCT's since it does this even when they are disconnected. This only happens under load in reverse or drive.
What I've ruled out:
1. I removed the rear drive shaft and inspected the u-joints. All seem fine.
2. Tested the rear differential by spinning the tires forwards and backwards on both sides. Everything seemed to turn without a problem and without weird noises.
3. Replaced all spark plugs, coil packs, and fuel injectors when I bought it (126,000 miles) so I don't think it's a misfire. Also, there doesn't appear to be any misfires per my scanner on mode$6
4. Checked the IWE's and found one side was not spinning freely. I replaced both IWE's and vacuum solenoid. Both front wheels work as they should now.
5. The transmission shifts great up and down when giving a good step on the gas pedal or when slowing down.
In summary, I believe this may be a torque converter problem, but I don't know if these problems could also be related to the transmission or a failing transfer case, or perhaps a bad bearing on the rear differential.
Thank you all for your help in advance.
Car description: I have a 2006 expedition with the 5.4 3v. The truck currently has 143,000 miles. I bought it when it had 126,000 and the transmission was never serviced until I bought it (found the little transmission plug at the bottom of the pan). Since I bought it, I've done the transmission drain fill and filter change twice. Also, I made the mistake of removing the transmission bypass when I replaced the transmission lines (around 140,000) so in the winter I have to warm-up the truck 5 to 10 minutes before driving it otherwise I get a very rough shift and bang when going from first to second gear. I live in Virginia though, so I was under the impression that it didn't get cold enough to damage anything internal (perhaps I'm wrong).
The problem:
1. momentary rumble sound/feeling like I'm going over a pothole or rumble strips. This mainly happens when going above 40 mph and only does it when I've stopped accelerating and tapping the gas lightly to cruise.
2. Loud bang when shifting into drive but much more pronounced when shifting into reverse.
3. The truck will tend to roll forward if I'm backing up my driveway and let go off the gas or similarly roll backwards if I'm stopped on a hilly road.
4. If I'm stopped and lightly press on the gas the truck will rev up fine but will throttle down quickly. This sort of feels like a misfire once I let go of the gas. It almost feels like the VCT's advance timing but then abruptly close, but I've ruled out the VCT's since it does this even when they are disconnected. This only happens under load in reverse or drive.
What I've ruled out:
1. I removed the rear drive shaft and inspected the u-joints. All seem fine.
2. Tested the rear differential by spinning the tires forwards and backwards on both sides. Everything seemed to turn without a problem and without weird noises.
3. Replaced all spark plugs, coil packs, and fuel injectors when I bought it (126,000 miles) so I don't think it's a misfire. Also, there doesn't appear to be any misfires per my scanner on mode$6
4. Checked the IWE's and found one side was not spinning freely. I replaced both IWE's and vacuum solenoid. Both front wheels work as they should now.
5. The transmission shifts great up and down when giving a good step on the gas pedal or when slowing down.
In summary, I believe this may be a torque converter problem, but I don't know if these problems could also be related to the transmission or a failing transfer case, or perhaps a bad bearing on the rear differential.
Thank you all for your help in advance.
