Hi all-

93 F-150 Automatic Tranny
175k miles

As I was driving along at about 35mph my rpm gage would go up to around 1.5X then drop to 1X etc and would sort of continue this as I mildly accelerated above 35mph. I also noticed it also at around 50mph too.

This has gone on only a couple of days. These same days the "CHECK ENGINE" light would also come on but would only stay on for maybe a 1/2 hour and then go off.

Doing an internet search - I was informed that maybe the internal computer diagnostic thingy could be malfunctioning and should be checked as it could be misinforming the tranny etc. (hope this makes sense. Im not a mechanic sorry so dont know all the lingo)

I did check the fluid levels and they were NOT even registering on the stick. Ugh! So i added more slowly, checking often and it finally registered normal once I added 1 entire quart! I havent driven it much since so i dont know if it has solved the problem (but obviously not solved the leak etc)

I climbed Under the truck and there is T-fluid sort of all over the area in the back where the vertical gasket/flat-plate (not sure whats its called) is located. I dont see any fluid further forward. It IS splashed back toward the rear of the truck too, but I'm sure this is just from the wind and forward driving motion etc. I didnt observe if it was actually dripping once i had added the new quart etc, but it may have been a little. (not a continuous drip, but more occasional) So since its more "occasional" it leads me to believe it has been dripping for awhile in order to leak out an entire quart etc.
Does this sound MAJOR or is this a possible gasket leak or something not tightened??
A few notes as to the history of the truck. Its been well maintained. The 4 wheel drive is seldom used (maybe 10 hours a year). However the last couple months it has been used more so and for longer than several hours at a time.
Less than a year ago, I had the fluid and filter changed.
About a year ago, also, it had been driven on DRY pavement for 1/2 hour while in 4-High at about 55mph. The tranny(?) smelled hot when i pulled into the house so not sure something was damaged or if thats just typical of running it hot etc.
Any help or comments would be appreciated.
Do you think the diagnostic thing is still needed even though I know I have a leak?
Is it ok to run while i have a leak as long as I make sure the fluid levels are ok and keep adding when needed?
What kind of a cost guess would you think is needed to fix?
Thanks to you all, Im sure your much more knowledgeable than I am on this subject and would appreciate your input.
Regards,
Norm Miller

 

1 quart low for a while probably will not hurt the transmission. you can drive it with a slow leak, just monitor as you said. the cost will probably depend on where the leak is. the transfer case (4 x 4) bolts to the back of the transmission, then the drive shaft sticks out the back of the transfer case. is the leak on the back of the transfer case, or between the cases. If between, you will probalby need to pull the transfer case to replace the gasket. that will take some time. might be easier to drive by a shop and let them crawl under and give an option and cost. washing things off first is a good idea, then after driving 5 miles at slow speed, see where the leak is before it blows all over everything.