could it be the range selector?
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Joined: Aug 2019
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could it be the range selector?
Hello I have a 1997 f-150 4x4 with a 4.6/automatic transmission. The issue is you can drive the truck for about 100 yrds shifting just fine then if you stop and then try to go its like the transmission has burnt up and will not move. If you shut the truck of and set for 15 seconds restart the truck you can drive about the same distance and it will do the same thing. If you repeat the process you can drive it again. The previous owner put three transmissions in it so i feel it is either the range selector or possible pcm. Am I on the right track or am I missing possibly a different sensor? thank you
Lead Driver
Joined: Sep 2006
Posts: 7,907
Likes: 143
Any of these issues are electrical.
The PCM monitors all of them with an assigned code for each function.
You must look at code when the issue is present, otherwise it's just guessing like the previous owner did.
The trans is electrically controlled hence the ability of the PCM to monitor.
No codes makes it a likelihood the TRS is not properly adjusted mechanically such that it is not fully in gear or a trans mechanical issue the PCM cannot detect.
What does Low gear only do?
What does reverse do?
Was the correct transmission installed so the plug up pins all match? A code would be set if not.
If the failure is when upshifting is commanded, then an electrical failure would be the suspicion. Inside 100 yards you don't really get up to speed full upshifts.
You need to think in these terms and not guess.
Good luck.
The PCM monitors all of them with an assigned code for each function.
You must look at code when the issue is present, otherwise it's just guessing like the previous owner did.
The trans is electrically controlled hence the ability of the PCM to monitor.
No codes makes it a likelihood the TRS is not properly adjusted mechanically such that it is not fully in gear or a trans mechanical issue the PCM cannot detect.
What does Low gear only do?
What does reverse do?
Was the correct transmission installed so the plug up pins all match? A code would be set if not.
If the failure is when upshifting is commanded, then an electrical failure would be the suspicion. Inside 100 yards you don't really get up to speed full upshifts.
You need to think in these terms and not guess.
Good luck.
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,739
Likes: 2,669
From: SE Florida
It can't be the range sensor. No matter what the range sensor tells the PCM you will still have first gear available. If the range sensor says N or even park the trans will just stay in first gear. The range sensor cannot force neutral. In fact, it cannot be ANYTHING electrical. This is the result of a mechanical problem. Low fluid, internal filter problem, too much junk in the filter, worn/leaking clutch seals, etc.
Fleet Mechanic
Joined: Aug 2002
Posts: 1,900
Likes: 29
From: Raleigh USA
You said 3 transmissions have been installed but was the cooler flushed or replaced? Were the transmissions reman, rebuilt, or junkyard pulls? How does the fluid look? Color? Odor? When I went to trans school the instructor told us it takes 3 transmissions to properly flush the cooler. Obviously he was joking trying to emphasize flushing the cooler or replacing it is very important to the new transmission.
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fordranger94
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Nov 15, 2018 06:13 AM
