91 Explorer Transmission Advice please
 

I would like some advice from anyone that has experience with Explorer transmissions. My first transmission went out at around 82,000 miles (wouldn't go into 3rd gear). I had a rebuilt one put in and I'm up to around 89,000 miles but it seems to be slipping when cold. The rebuild is out of warantee so I haven't had it back in the shop yet to have it looked at.

What do you think the likely causes are? I checked the fluid, and it is clean, and full. Can this tranny be adjusted at a shop for low cost for this kind of problem or do you think it's on it's way out?

Also anyone that has had success with these transmissions, what kind of maintainence did you do on them? I have a 02 Explorer, and want to treat the transmission with the best of care, since it appears to be a weak link in my 91.

Thanks!

91 Explorer Transmission Advice please
 

My first Explorer was a 1991. When I sold it, it had 118,000 miles on it. NEVER had any problems with it at all.Great Truck. Can't imagine why you would be having problems,I will however, ask around.Any chance,when putting it into 4-wheel drive, you may be not be doing it correctly?? I had some problems with my 1997 Explorer, OD light blinking, Never found a cause for it, but I would disconnect the battery for 20 seconds, then re-connect it, and the light would go out. I sold it last December with 57,000 miles on it.
I bought another 1991 Explorer w/ 70,000 miles on it, from a dealer going out of business. I loveit!! The older syles 1991- 1994 are much better looking Trucks. I have never heard of anyone having problems with the transmissions in the older syle Explorer's.

91 Explorer Transmission Advice please
 

I have a 92 (late 91) and the overdrive went out around 80k. That was a defective weld on the OD planetary assy. Had a cheap rebuild done on it and 14 months later, OD went out again. Thought, heck, I'm just going to drive it till it blows up. So I drove it forover 4 years and 70K that way changing the fluid and filter every 6 months with 5 extra magnets in the pan. Stopped driving it when the fluid started looking like motor oil in a month. I still drove just fine except no overdrive. Now I'm rebuilding it (that's I, me, and myself) and have found that the OD clutch drum snapped the castle teeth and ground up the star washer. These transmissions are rather easy to rebuild. In spite of what people say, if it wasn't for parts in the OD snapping, this could be a very reliable transmission. At 200k, the clutches are still perfect. Here are the common problems:

Torque converter: Early ones weren't brazed and the TC clutch wears out. If clutch goes, engine rpm 300-500 higher than before.

Overdrive parts: Drop transmission, unbolt the bellhousing and these parts are the first parts out. No special tools needed. About as hard to replace as a starter once the transmission is out.

Low/Reverse servo: If it is slow to back up or if you drive it down hill in 1 and there is no engine breaking, you can fix this (change two easy O-rings)for under $50. Almost everyone needs this and doesn't know it. Takes as much skill as replacing the filter. Just drop the pan to get at it.

Clogged filter: Hard to shift when it's cold. Change filter and fluid. It will buy you some time but you got something grinding and clogging the filter.

Speed govenor: These start sticking at about 150K. Cause late shifts from 1 to 2. The tail end of the transmission unbolts and you polish the piston. Not a tough job. If you have the skill to do brakes you can do this. Late shifts can also be caused by the vacuum modulator, another external device. Check vacuum tree on engine for signs of oil.

So what exactly is this slop and what is the color of the fluid?

91 Explorer Transmission Advice please
 

Thanks for the good info. You make it sound so easy that I would be tempted to try :) Although I haven't done anything that complicated before. I've only worked on things like oil pan replacement, starter, alternator etc. The easy external stuff. Never even done breaks, but would be interested in learning how to do that if it's relatively easy to do. My wife burns up break pads pretty quick.

>So what exactly is this slop and what is the color of the
>fluid?

The color is red, and clear. The slop in the tranny occurs first thing in the morning, the RPMS need to rev around 500 higher than I would expect so there isn't as much torque or power to the road. This lasts for about a block or two, and then things start tightening up.

This car has been a late shifter for awhile and I think that might be a vacuum problem because when it won't shift from 1st to 2nd, I will rev it then let off the gas quick and then that usually makes it shift. Does this sound like vacuum to you?

I guess I will take off the pan off the tranny to replace the filter. What should I look for once I have the cover off? Any other suggestions are greatly appreciated.

Thanks!

Rick

91 Explorer Transmission Advice please
 

The following is copied from another post of mine. More information is also available from www.atcdg.com click on tech and view A4LD problems, in particular low/reverse. Try the hill test in 1. There will be some metal particles and tat will be ok. Check for things larger than dust. Buy some ceramic magnets from Radio Shack and put them in the pan. The idea is keep this stuff out of the valve body. Ts this 2WD or 4WD? The filters were different in these older ones and the fiber one could be clogged. Have to do that hill test before dropping the pan!

Another improvement is the American made glass fiber MicroFelt filter from SPX/FILTRAN.. This is also the same filter that is used in the 5R55E (#23921 for 4WD). If you have shopped for filters previously, you will remember that the 2WD versions got the filter element and the 4WD versions got just a metal screen. Evidently 4WD vehicles needed a higher flow for better cooling/shifting. The new filter is physically much larger than the old filter. There is even more filter area because the filter is folded over and welded inside to create twice the surface area. Flow restriction is no longer a problem with this filter. Be sure you order the correct long or short tube version depending on your pan design. This filter is only about $10 from www.bulkparts.com and comes with a new bolt and spacer. If the filter is ordered separately, it does not come with replacement O-rings or a pan gasket. These seals are included in the overhaul kit. SPX/FILTRAN.technical details can be viewed on www.bryco.com. SPX has the patent on this filter design #D422600 and many others.

91 Explorer Transmission Advice please
 

Thanks for the info Opera! Since I haven't ever taken the transmission pan off before, I have some other questions.

1) How can I tell which pan I have, and therefore which filter I need? I have the 4WD, so I guess the part number you gave me is correct.
2) Since it doesn't come with gaskets and O-Rings, which ones do I need? I found # 23270 on bulkparts that looks like it might be what I need.
3) Besides magnets, are there any other parts that I need?
4) Can you give me the steps to dropping the pan and replacing the filter/O-rings? I don't even know what the O-rings are for.
5) Do I need a torque wrench for tightening the pan bolts? Is there a specific order to tightening them, or for that matter, loosening them?

Sorry if the answers are obvious, but having never done this before, I want to be prepared when the time comes. Nothing worse than dropping the pan and missing parts that need to be ordered.

Thanks again!

91 Explorer Transmission Advice please
 

Just time for a quick message. On the filter, there are two O-rings tat can be transfered from the old filter. Believe these are indicated on bulkparts as a large and small. I have never purchased these as a seperate item and have transfered them from the old filters, but you should have some just in case. I have an O-ring kit for emergencies.

91 Explorer Transmission Advice please
 

I think I found the parts I need and will order them. In the mean time, I have been continuously checking the fluid level, and it is high. At first I thought I was measuring it wrong so I wrote it off. But now I'm pretty sure it's too full. What is a simple way to drain some of the tranny fluid without dropping the pan? I would like to see what affect setting the correct level will have on the way it is performing.

Any ideas on lowering the level SAFELY? Can I just remove the return line to the front cooler and let it drain while the engine is idling?

91 Explorer Transmission Advice please
 

High fluid level should not affect the operation that much. It would cause foaming and might push fluid out the overflow tube. You can remove fluid by disconnecting one of the radiator tubes. THIS IS VERY DANGEROUS. When I put in a new radiator, these connections were stuck and it took cutting the radiator open to remove the adaptors. Twisting could cause a small crack between the coolant and the fluid. If you have a trans cooler, remove the rubber hose or forget it. If pan gasket wasn't that old you could just drop the pan a little. Your gasket will probably crack. Wait till you get a new seal.

91 Explorer Transmission Advice please
 

My Radiator was recently replaced, so I would guess that the connections wouldn't be stuck. Besides the stuck connection, do you see any other risks?

Also for the pan gasket, bulkparts lists two, one that is listed as cork and rubber, and the other is "Farpak black gasket". The latter is more than 2x expensive. Is this a case of you get what you pay for or is the cork and rubber good enough?

Here's my list of things I'm purchasing (all from bulkparts.com):
1) Filtran Filter (item #23921)
2) Two Pan Gaskets so I can decide later which to use (Item #'s 32141D, 23141)
3) Small and large Filter O Rings Item #'s 23270, 23271.
4) O Ring for the filler tube, item 25266.

Am I missing anything here?

Thanks for your advice thus far, it has been invaluable for someone like me who has the desire to do it, but not the know-how!

91 Explorer Transmission Advice please
 

so you can support the adaptor at the radiator and keep it from turning. There are some small 1/4 inch hard plastic tubes that can be found at hardware stores that could be used to suck the fluid out. I use the cork and rubber gaskets and they seem to last through several removals. I would order the manual if you are thinking of getting serious. It takes a couple of weeks of reading before it all sinks in. None of which makes much sense till uou start to take it apart. Bulkparts web site is very for the neophite. It's got pictures and prices (really good ones on tech manuals). Once you are more familiar, you can shop some of the others for hard parts. I'm lucky that I have a Transtar distributor in town. Shipping a torque converter can eat up any good deal you find. Got my TC for $105 out the door exchange. Best price before that was $137 + $35 shipping + $50 core. Why ship a core back to get $15. Got the rebuilt OD drum for $65, this has a $6 core charge or $130 new. Don't see why you would need fill tube o ring. If you really think the OD is gone you should get the basic seals and gaskets kit. Don't buy any clutches till you open it up, they are probably still good. Did you see those other posts? I wrote one Earth Transmissions are Easy.

91 Explorer Transmission Advice please
 

I forgot about getting the manual. With their shipping costs, I was trying to get everything in one order. I will probably order it, but want to make sure I get everything I need before then. The parts won't arrive until next week, so this weekend isn't in the cards for opening it up anyway.

I probably didn't need the Filler tube O-ring but it was so cheap, I figured it was easier to have too many rings than not enough. Can you tell me what the gasket kit part number is on bulkparts.com so I am looking at the correct one?

What kind of things would you expect me to see when I drop the pan if there is something wrong with the clutches or overdrive? Can I inspect most of what I need by just removing the pan and filter? My current plan was to just replace the oil and filter, on the chance that it was contaminated with radiator fluid with the bad radiator, but I would like to look for obvious things. Would I need that book to know precisely what to look for?

Don't remember seeing the "Earth transmissions are easy" thread.

91 Explorer Transmission Advice please
 

All you will be able to see is the valve body and the filter. If you snapped something is the overdrive there will be some metal particles. I even found roller pins once. Coolant could cause one of the bores (control valves) to stick. Several of them you could stick a probe in and physically move them. The manual would tell you which one it is. The brake inhibits overdrive. Should have told you this before. Check brake for a switch that might have popped out of place. Prefer to continue this where I usually am. Trying to keep A4LD rebuild an active thread and as a central source for information.

91 Explorer Transmission Advice please
 

>>Prefer to continue this where I usually am. Trying to keep A4LD >>rebuild an active thread and as a central source for information.
I'd be happy to go wherever you are, just need a pointer.

Thanks

91 Explorer Transmission Advice please
 

Clutch Piston Snap Ring Removal
On the internal clutches, the snap ring is retained by a metal lip or posts on the spring retainer. It is necessary to push the outer edge of the spring retainer down about 1/4 inch to remove the snap ring. The ATSG manual shows a nifty tool to do this but a variety of home made devices could do this. It could be as simple as using a nearly empty mylar shipping tape spool, as I did one night. Or a small board with 4 or 6 long screws paced in a circle. I fabricated one out of a 4 inch diameter thin wall steel tube that was 2 ½ inches tall. A section of the sidewall was cut out so the tube could be bent to 3 ½ inch diameter. Basically, ovals were cut out of each side for viewing and tool access. That left nearly a complete ring on the top, so the device stayed in one piece, and two half moons on the bottom. A vertical column on each side supported these wide feet, much like the one pictured in the manual. This design is easily bendable to fit different diameters. The compressive force is supplied with two bars pulled together with a long bolt. The top bar is 5 inch and threaded for the long bolt. The bottom bar is 3 1/4 inch with a clearance hole for the bolt.. It takes very little effort then to remove the snap ring. Once you have removed the ring, the need for the retainer becomes obvious. Care should be taken when the rubber sealing rings are removed to note the direction of the sealing lip. Put them in backwards and you won't have much of a seal. Great care must be taken when reinstalling the snap ring. Visually inspect that it is properly seated. Push down on the edges of the retainer and the snap ring to see that it is all the way in. This was considered such a problem that they redesigned the retainer into a continuous lip instead of the posts in later versions.

The clutch plates, friction and steel are easily removed prior to the piston removal. The snap ring has a small lip on one end which can be caught with a small screwdriver. This is followed by a thick pressure plate and the alternating friction and steel plates. There is usually the same number of each but if the transmission has been rebuilt before, there may be an extra plate (.070 inch) to take up some slack. A clear sign to install new friction plates. This is the poor boys adjustment instead of installing a thicker snap ring. When the clutches are installed, you are looking for a clearance of about 70 thousandths (.055-.079 inch) between the snap ring and the pressure plate for all three clutch packs. You not only have to push down on the clutch pack to make this measurement but lift up on the snap ring New friction plates should be soaked in transmission fluid at least an hour before assembly to insure proper thickness.


Overdrive clutch had a retaining ring thickness of 0.0681and I had about 40 thousandths clearance with all used plates. Installed three new steel clutch plates (which were slightly thinner, Allomatic) with the old friction plates and got the required minimum clearance. This was the rebuilt drum from Transtar Industries and doesn't use a full complement of springs (install three springs and skip a spring) . One down, two to go.

Reverse-high clutch had a retaining thickness of 0.0681and I had less than 40 thousandths clearance with all used plates. Again, installed six new steel clutch plates (which were slightly thinner, Allomatic) with the old friction plates and got the required minimum. This was from the transmission rebuild in 96 and wasn't checked too closely. Two down, one to go.


Forward clutch, the one with the rubber cushion, had a retaining ring thickness of 0.0819 and had more than 110 thousandths clearance on all used plates. But then, just how do you measure that when you are gauging against rubber. The interesting part was that this clutch had 5 friction plates and 6 steel plates. Although the friction plates showed no more wear than the others, this drum had the most friction material sediment. All friction and steel plates were all replaced. This time I was able to install six of each and still have the minimum clearance. This piston has the largest surface area of all the clutches and uses the flat sealing rings that don't have any install direction. For this piston, only the two bars and the screw were needed of my home made tool for removal.

The tightness of two of these clutches were probably the cause of the fluid blackening the first six months of operation after the rebuild in 96. Glad I found a use for the steel clutch plates, though it was never the purpose I imagined.