I am getting NO overdrive (ever) in my 1992 Ford Explorer (A4LD). In this year the only thing "computer" on the transmission, as I understand it, is the sig to the 3/4 overdrive selenoid. I noticed the problem seemed to start, a few week ago, when I saw my mpg record drop from 15/16 to around
13mpg, and saw that at 70 mph my tach was reading >3k (at speeds over 70 it doesn't drop below 3k at all and heads toward 4k without dropping).I had a rebuild at 56k miles and I now have 82k miles. The truck is in very nice shape and I think I could keep it except for these transmission problems. Of course, I'm reluctant to spend $20 or $30k on a nice new vehicle, but I don't want to pour money into new transmissions every 20 or
30k miles....I also had (also noticed a few weeks ago) a slow 1/2 shift when the truck was cold, but fortunately that was cleared up with a tranny service a week ago. I had the service done at a tranny shop (different from the 56k rebuild place) and they said there was thrust washer metal in the pan....
From what I've read the service with new fluid probably cleared up some minor governor muck inhibiting the 1/2 shift (ONLY when the truck was cold and ONLY w/i the last couple of weeks). From what I've read about the Explorer, A4LD's, and heat effecting tranny fluid, I would probably get an external tranny fluid cooler (big) and filter with a rebuild AND I WOULD CERTAINLY DO A TRANNY FLUID/FILTER SERVICE EVERY 12K MILES FROM NOW ON (even though Ford says 30k).
I was told the transmission would fail, but I might be able to drive it for quite a while or it could go tomorrow. I was told the price of a rebuild wouldn't be much different, except for a tow, if I just drove it until it goes. I'm putting less than 5k/mi per year on this vehicle now. I DON'T want a really unreliable vehicle. If I'm going to "fear" driving it I will either dump it or rebuild the xmission.
I'm going back to the 56k rebuilder for a "test" which, I presume, will be as in a post:
" all,but lets say that is the case.....that would mean that the computer is reacting on data it is receiving and the data would be false....In 4th gear at
70mph,you have both shift solenoids (on valve body) energized....for some reason data is being sent to computer to release one of the solenoids....it is possible that the computer is being sent erroneous signals from the speed sensor....at 70 and the computer sees 10mph, then transmission will try to go to first gear.....you will not feel it as a downshift, but as a simple neutralling condition.....also there could be a defective shift solenoid.....with a scan tool attached to obd connector,one will be able to determine if the command for fourth gear is being made at 70.....if the command is there,then the problem MUST be internal...if the command is not there,then there MUST be a vehicle sensor at fault or bad computer.... goodluck"From everything I've read I'm thinking it's either the 3/4 selenoid (or wiring to it), or a bad VSS or TPS confusing the processor or a bad processor, or (dread) bad workings inside the tranny (the shop that looked in the pan didn't see any "band metal").
I'm not having any slipping and, except for the no OD, it works fine. My thinking is that if I could just drive the Explorer the way it is I'd leave it alone. With the few miles I do the wasted gas without the overdrive doesn't amount to much.
Now, a few questions:
- Any benefit to drive in "D" rather than "OD" (there is no OD "button" or light on this "non-electronic" Xmission) regarding the longevity of the transmission, the way it is with no overdrive ?
- Is there a way to get an A4LD rebuild for a '92 Explorer that I KNOW will get 40 or 50k miles (which would motivate me to have the work done). The standard rebuild Warranty here in the San Francisco Bay Area is 3yr/36k mi. With the few miles I drive the Explorer even 50k on a rebuild would probably let me keep the truck another 10 years (we don't get any rust in our "no snow no salt" part of the country). Of course, we really can't KNOW much in this life, but I'm reluctant to play "Exploader" Roulette with the ~,500 a rebuild is costing in this area; 26,000 miles on a rebuild, as I experienced here, is unacceptable to me.
- With NO tranny slip or other faults than the OD problem any "guesstimate" on how long (time/miles) I could drive the truck if it IS an "internal transmission problem" ?
- Can you get OBD readings for these problems in an earlier Explorer?
- Any other thoughts on all of the above would be greatly appreciated.
Thanks in advance,
Bob G
PS: I'm unable to do any of the work myself as I really don't know anything about all this, except what I've researched in the past week or so.