Transmission Problem

[jtillery]

I purchased a 2000 Explorer Sport 2wd with 106,000 miles a couple weeks ago. When I was test driving it, the shifts were very firm and it had a little flare between 2-3. I got the seller down on price (which was already real low) so I decided to buy it anyways. I have been doing a ton of research and it seems like a VB rebuild is probably in my future. I am almost certain it is the 55r5e transmission.

The tranny fluid is brown, but doesn't really smell burnt, the level was also high, maybe 1/4"-1/2" above the full mark when hot. Every gear seems to work well without slipping. It also seems to be engaging at the right points. I have driven it about 500 miles since I bought it and the shifts are much softer now, seem like they are normal. (I have a 95 Explorer Sport to compare to). In between 2-3 it will rev up 400-500 RPMs most of the time, especially at small throttle openings. At 1/2 - 3/4 throttle it doesn't flare. Twice since I have had it, it sounded like there was a slight grinding between 2-3, seemed like it didn't engage at just the right time.

With the condition of the tranny fluid, it seems like a flush would be the best bet. However, I do not know if and when it was every serviced before. I was thinking about following it up with a second flush in case there is a bunch of crap floating around. If I go that route, how long should I wait? Or since I don't know the history of it do you think I would be better just dropping the pan and changing some of the fluid? I was also considering putting in some Lucas additive.

I am trying to decide if I should change the tranny fluid, or just go ahead with the VB rebuild. I guess I know the fluid is in rough shape, but don't know if that would have a big enough impact to be causing my problems. Should I try the fluid change first (if so, flush or pan drop) or should I bite the bullet and do a VB rebuild and fluid change at the same time?

The only history I know is it has 106,000 miles and it pulled a decent size trailer at some point in its life (it has a class III hitch and elect brake controller).

Thanks,
Joe

 

[vanionBB]

You could install a 2nd transmission filter along with a fluid and filter repalcement. The 2nd filter uses a regular oil filter and it continually cleans out the fluid.

Definetly change out the fluid though, you can do a flush, pump out the old and pour in the new as it pumps out. Flushing is a little easier with the 2nd filter though you will still have to manually fill up the fluid through the dipstick tube, I used a 5 gallon bucket and as 1 quart was pumped out I would pour a quart back in thru the dipstick tube, if you get behind shut off the truck and catch up. When the fluid came out red I was done, took me about 13 quarts of the cheap walmart brand but it works

 

[BrooklynBay]

You should drop the pan, and replace the filter. If the filter is partially clogged, it will drop your hydraulic pressure, and cause your soft shifts. Use Mercon V only. Any other grade of Mercon, like Dexron III/Mercon is not for your year (2000), but is for your other vehicle (1995).

 

[BrooklynBay]

Mercon V has special friction modifiers that are made for this kind of transmission. If you use Dexron III/Mercon, you will need a special friction modifier that is made by Lubegard. Check the transmission fluid application chart in my signature. Using the wrong fluid has been known to cause dirveability problems.

 

[jtillery]

If the filter is partially clogged, it will drop your hydraulic pressure, and cause your soft shifts.

The shifts feel normal now except for the 500 RPM 2-3 flare. When I first drove the car they were very firm, it seemed like it was in limp mode. No codes showed up though.

Is it possible for the fluid (high level and dirty) to cause the 2-3 flare? If it is, I will change the fluid now. If not, I am thinking it would be best to rebuild the VB and change the fluid then. I plan on having the car for a few years so I don't mind putting the cash into the VB rebuild if it is needed.

 

[jtillery]

You could install a 2nd transmission filter along with a fluid and filter repalcement.

That is a good idea, I will definitely look into doing that.

Definitely change out the fluid though, you can do a flush, pump out the old and pour in the new as it pumps out.

Do most people do this themselves, or take it to a shop to have it down? I think I could get it done for under $100, and for that I don't know if it is worth the hassle. My guess is it would cost $50 or so to do it myself...

 

[jtillery]

Mercon V has special friction modifiers that are made for this kind of transmission. If you use Dexron III/Mercon, you will need a special friction modifier that is made by Lubegard. Check the transmission fluid application chart in my signature. Using the wrong fluid has been known to cause dirveability problems.

I read several discussions on that. I will definitely be using native Mercon V fluid.

 

[BrooklynBay]

Dropping the pan, and replacing the fluid only drains out a part of the existing fluid, but not everything. One way to do this would be to have an assistant start the vehicle while you keep pouring new fluid into it while the old fluid is being drained out into a container. If you can't do it fast enough, then your assistant could shut off the engine while you are getting another container. This method will completely replace your existing fluid. I've read some stories about people flushing their transmissions with a flushing machine, and then the transmission failing shortly after. The only possible explaination would be that the new fluid has a lot of detergents, and might have caused some fragments that were preventing leaks to get washed off. The old fluid has a lot of small particles floating inside of it from the clutch plates, and metallic dust. Too much of this stuff could cause clogs in a filter, VB, cooler, etc. If you replace your fluid regularly, then a flush shouldn't harm anything. If you have the same fluid for many miles, and haven't maintained a fluid replacement routine, then you might be better off dropping the pan, and replacing the filter. You are still replacing some of the fluid, so it should be a little cleaner.