06 6.0 f550, service body and constantly loaded heavy.
This will actually be my 3rd post in about a week and a half, all unrelated and the first two resolved. (Broken differential ring gear bolts, then a seriously over thought turbo boost problem).
Last night heading home from the last job of the day, reasonably flat road here in Kona (45 mph zone, low grades) I heard a noise like a rock hitting the bed (anyone with dual rears knows that one) only smaller. Then had a sense of unease about my trans that I cannot really explain, perhaps a late shift or slight slip? Nothing I can actually put my finger on, but I am usually one with my machine, if you know what I mean.
Heard the noise a second time and pulled off the road. I saw a lot of gravel in the treads of the steering tires and convinced myself that this was the culprit. But it seemed like the trans was making an odd noise that I can only equate to power steering noise.
I checked the dipstick when I got home and all seemed fine.
Rolled out this morning and at my first shift 1-2 it felt like it did not engage. This was on a slight downgrade, but my spidey senses were tingling, so I got off of the road and played with the shifter.
Severely slow engagement from park/nuetral to drive or reverse. Checked dipstick again and it looked low so I added 2 qts spring and then it seemed to shift correctly. I can see no signs of external leakage. Played with it a bit and the slow engagement happened again. Drove until it tried to shift into second and did not like the engagement so I shifted down to first and limped home to do some pressure testing.
No current dtc's, but I have had an intermittent p0741 tc
clutch lockup code that I was hoping to wait to work on until after I get back from vacation at the end of next month.
My line pressures are goofy. Initial testing at idle was
P,N 50 psi
with regular spikes to 120
R. 110, spiking to 180
3 and 2, 70
Throttled up I got:
D. 250 with a squeal
I have been waiting for a friend to show up who has better diagnostic equipment than I do in order to check the electric side of things (I am primarily a heavy equipment mechanic) so I have not pulled the pan yet to look. I did drop a small sample of the oil and it is darker than I would like.
My pressure in park right now seems low and spiking fairly regularly (20 to 150 in park at idle)
Right now my thinking is oil contamination or stuck PC-A solenoid, but the pressure spikes have me considering cavitation. Either way I am ready to pull the trigger on ordering a new trans and TC
from Ford unless someone can talk me out of it.
I know that might seem like overkill, but I fly out of the country on Friday for a month and that means when I get back I will be about 2 months behind.