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rvinit's avatar
rvinit
Explorer
Nov 09, 2015

Transmission slipped temporarily(?)

Hi all,

I've put about 500 miles on my '94 HR Imperial with 60k miles and the Ford 460 engine.

I've only seen my transmission temp gauge move above 100 degrees one time, and it was only slightly. When I put the key in the "on" position, I see the needle twitch a bit... but here's what happened:

I towed about 60 miles the other day (little Chevy Sonic on a car dolly) to my home for the next few weeks. Parked for about 20 minuteo, did some check in and walked around, disconnected my car and trailer, then drove across the street and backed into my space. I turned the engine off and decided I wasn't happy with my placement.

I started the engine, dropped it into reverse, nothing. Revved a little, nothing. Switched to drive, nothing, neutral, back to drive, revved to about 2500 and heard the trans catch and I started moving forward. Threw it in park immediately. Noticed the smell, opened my driver door and saw white smoke rising up. Engine temp around 230, trans gauge still showing under 100.

I let everything cool down and inspected for leaks, can't find any evidence of one. Got engine up to temperature two days later and checked tranny fluid - it's clean, red, and filled appropriately. I put the home in drive and it engaged immediately and pulled forward. Reverse was the same.

I'm concerned now because it's acting as if nothing ever happened and I've done nothing to figure out what this could have been. Any suggestions about where to start? I'm going to pick up another transmission gauge tonight to test with, just to be sure...
  • If your gauge never read above 100 degrees, either the gauge or the sensor is defective. I would guess that normal temp on a level road would be 150-180 degrees.
  • When was the last time the transmission was serviced?
    Filter cleaned/replaced?
  • Clutch plates in the transmission were not engaging. Low fluid, dirty fluid, clogged filter, bad modulator, all sorts of possibilities. When transmission fluid burns, white smoke is seen. Best to have an expert look at it.
  • gbopp wrote:
    When was the last time the transmission was serviced?
    Filter cleaned/replaced?


    I really wish I had those details. I have maintenance records up to about 25,000 miles and that's it. The last 500 were me, leaving a large gap.

    I'm going to replace the gauge (and sensor if that doesn't do it) next weekend, along with oil and coolant flush. I'm hoping I may have just pushed it a little bit too far.

    I'll schedule an appointment somewhere to get the transmission worked on, that's one thing I am not familiar with at all (this is actually my first vehicle with an automatic tranny). I guess I realized I'd rather pay a bit now to have some work done preemptively than wait for it to outright fail.. was just hoping to narrow down what could have happened that would have made it slip with appropriate fluid (that looks clean)... yet work just moments later.
  • Given the age of your rig I would guess a filter issue. Auto trans need fluid and bad filter will slow the return of atf to the pan. A good cheap check is Blackstone labs. For $25.00 they will send you a bottle fill and return it. They provide you with a detailed analysis of your trans condition from chemical conditions of the fluid.
  • Just a guess but, it sounds like something with the torque converter.
    It's best to have a transmission person look at it.

    Please, keep us updated.
  • I had an E350 with a 400 and C6 tranny.
    I once pulled a heavy flatbed loaded with sheet rock up our lane at about 10mph, obviously the torque converter wasn't in lock up, when I got up the hill with it and then tried to back a short distance up to our garage the van wouldn't budge. No smell or other signs of over heating and it didn't have a temp gauge for the transmission.
    I let it sit for about an hour and then it backed up just fine and we never had any problems with it. But we were aware of what we had done and always tried to go fast enough to lock up the converter. Which is sometimes hard to avoid.
  • Check the Ford Diesel site thedieselstop.com and search for 4R100 problems when backing with a load. You experienced a common problem with that transmission due to insufficient cooling under load. I had a similar experience when backing a travel trailer up a hill with my F-250 PSD.
  • Thanks everyone. I actually have a Blackstone kit on hand for motor oil, might see if I can send ATF instead. I am scheduling an appt. for filter and fluid change, I will have them do a once over. I'll update the thread when I have information. My engine runs a bit hot too, which I'm sure contributed to the issue.
  • As you don't know when the ATF or tranny filter were changed, I would get that done.