After finally getting my f-150 running smoothly, the wife's explorer is now on the fritz. it's a '99 explorer limited V8 with 117K miles. this morning while driving her car to work, the o/d off light started flashing and the tranny started acting up (hard shifts, loss of o/d). once i arrived at work i checked teh tranny fluid, which may be slightly low, but is clean. so i unplugged the batter for 15 minutes, then drove to Kragen and topped off the tranny fluid. now the light is off, and the tranny seems to be running smoothly.

I'm wondering, will this problem reoccur once i've put a few miles on the truck?
Could i be so lucky as to just be low on fluid and should be ok now?

i've searched the forums and although this seems to be a common problem, i'm not seeing many solutions.

Thanks to anyone who has any suggestions!

-chris

 

I don't think low fluid would cause your problem. My OD light blinks on my 95 about once a year. I pull the codes (reveal nothing) and reset it and it's good for maybe another year. There are many posts on this forum about Gen II OD blinking lights. Some people have had new transmissions put in only to have the problem reappear. I suggest driving it and see what happens. Also, the 'hard shifting' you are referring to is Ford's 'limp' mode. It's not particularly good to drive it in that mode for long distances. It was designed to enable the drive to limp it into a repair shop.

 

thanks for the reply marragtop.

so, you think i should pull the codes even though now the light is off?

 

No, you've lost codes since you unhooked the battery. If it comes on again, pull the codes to see what they reveal.

 

i see. i will definately do what you suggest, but hopefully, like you, i won't see the light for another year!

thanks again

 

To krystov10, I've fought my 02' Explorer transmission for some time now and I feel bad about the confusion others go through with their transmission. The rapid flashing of the OD off light is the computer telling you that it has completely failed to control the shifting of the transmission and has put it into a failsafe "limp" mode. What's frustrating about the limp mode is that error codes are not always generated! Furthermore, the computer is only utilizing 3 speed sensors and a fluid temperature sensor to decide how well the transmission is doing. It is true that it can also monitor the electrical characteristics of the shift solenoids, but that is not the same as true feedback from actual monitoring sensors. I know this because I work on computer controlled air conditioning systems. You can deduce a lot of things from some simple information, but you can also be fooled greatly by what you think you are seeing.

Keep an eye out for the rapid flashing and see if it continues to happen. Maybe you'll get an error code or maybe not. The check engine light should come on if you do. Because it's an Explorer I would guess that it's devoloped a leak inside the trans causing low line pressure from the pump. If you can get a pressure gage temporarily installed on the trans you'll know if you do have a leak. There's a small bolt on the drivers side of the trans about 3/4 of the way back that is the line pressure tap. With a gage installed that can withstand at least 400 psi allow the trans to fully warmup and then have someone put it in drive or reverse with the brakes on and read the pressure while it's at idle. The pressure should be at least 90 PSI. If it's at 90 your marginal. If it's below 90 you have a leak that's most likely one of the servo bores.

Good luck!

 

wow! thanks for all of the helpful information. so far the o/d off light has stayed off, and the tranny seems to be operating smoothly. (it's the wifes car, so i personally haven't had a chance to drive in the last couple of days) i will drive it over the weekend and see if the light comes back on. if it does, i will definately try the below before taking it to the mechanic.

Thanks!
-chris

 

One more thing krystov10, If you have only marginal line pressure you have some time before the transmission becomes really bad. The Explorer transmissions have a bad reputation, which is rightly deserved, but they can be altered so that they will perform at the level they were originally intended for. Talk to your mechanic about what might be done during a rebuild, cause that's ultimately where this might be headed, and plan for some upgrades that will really help the Explorer trans last a long time. Your transmission with beefed up servo bore bushings made of brass or bronze and an aftermarket valve body could see the Explorer trans outlasting the rear differential.

Again, you have some time to do this if it's really going bad. If it is then start collecting the funds and make a plan with your mechanic about what will happen during the rebuild, because I definitely don't recommend that any Explorer transmission be rebuilt to the condition that it was when it left the factory because it won't last.

 

I had my A4LD rebuilt in my Aerostar, and talked to them about beefing it up. The owner of the shop told me that witht eh upgrades and improvement, I may be able to easily run another 200,000 miles or more without problems. The transmission is only weak in its stock form. The automakers have to compete on price, and that means that concessions are made. Since the transmission typically outlast the warranty, they really don't care if it fails after that. They obviously don't want a bad rep from a lot of failures, but they don't have to directly cover the replacement either. Transmission reliability on a long term 5-10 year basis is not a strong buying decision for most people.