I have a 99 f-250 with a v-10 and an automatic tranmission. I just purchased the truck and on the drive home I was cruising at 65 mph and the transmission came out of gear and the engine kept reving. I kept going for a while but it wouldn't kick back into gear. It wasn't until I completely stopped the truck and started driving again that it would start shifting. It was a 3 hour drive home and this continued for about an hour progressively getting better and better until it stopped doing it completely. The speedo goes nuts right after it happens as well. It is obvious that they pressure washed the engine compartment before I bought it because it was as clean as the day it came off the assembly line while the rest of the truck was still as dirty as could be. I used cruise control for a bit and it was lurching while I had it engaged. At first I assumed that it was a bad torque convertor but the truck runs and shifts perfectly the rest of the time. Has anyone else had similar experience? Any advice would be greatly appreciated!

 

Did you notice the abs light coming on?
could be rear speed sensor??????
But something fishy here because Ihave never seen the tranny go into neutral when that happens.
If the washed the engine ,there may be water in the spark plug holes.
It will cause misfires possibly being your lurging,but that also could be your speed sensor.Compressed air blow out around all the plugs.
Take a look at it ,its mounted on top of the rear diff ,clean all the dirt away from area before loooking at it.
Rich

 

Welcome to FTE Mustang.

With the speedo going crazy, the first though that comes to my mind as well is the VSS mounted on the rear differential sending a bad signal. Very common problem and a cheap fix at around $25.00 for the part from Ford.

 

But would the speed sensor kick the transmission out of gear? I believe I was in 4th gear at the time. I was cruising along and then it just jumped up to 6000 rpms and would not re-engage. Thanks for the help!

 

Thats what I said!
You could have a problem internal in the tranny.
But as said the rear diff is a easy fix!
Than a $1200 tranny
Rich

 

Thanks Rich, i'll give it a shot!

 

Post back and lets us know what it was.

 

VSS seems to have worked. I have only been able to do a limited amount of driving but I haven't had a problem yet. Thanks again guys!

 

Excellent.
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