toyota guy here. im trying to help a friend out, his explorer (2wd, auto, 99, xlt) tranny is acting up and trans shop says he needs a rebuild. hes considering getting a used one and swapping it in. my questions ...

- whats trans does he have
- how hard is a swap (ive done HG, clutches, etc. just never an auto trans)
- will one from ranger work

thanks got the help

They're not too bad, but not fun to swap. I can do one in about 6 hours if I have a lift and a tranny jack. But that is a 4x4, 2wd should be a piece of cake.

One from a ranger will work.

Better option maybe to go with a 700R4 and the AA kit.

Which Tranny? Well, what motor? V8 or six?

Well, if its a 2 door, its a V6.

its a 5R55E auto. I don't know how much fun it would be, its an electronically controlled trans, so theres all that to watch out for as well.

4 door, i know its not a v8

Tranny is a 5R555re55 or whatever the hell..... i know its got 5R55 in there somewere. :D Overall, they're not that great of a tranny. I dont know if id waste money on a used one- who knows how long it will last. If he gets it rebuilt, he really needs two things..... a cooler and a temp gauge. The stock cooler isnt enough.... add a good high dollar plate/fin style inline with the stocker. The temp gauge will let him know he's killing the tranny before he actually kills it. This is pretty basic tranny advice, and im sure you know this stuff already, but its got to be done on the various Explorer V6's trannies to keep them alive IMHO.

The 5R55E is an electronically controlled 5 speed version of the old Ford C3 pioneered for use in the Ford Pinto. It has been through considerable updating and strengthening, but it is still a weak transmission and has a general life expectency of about 90,000 miles.

There are several known issues with the 5R55E (and it's first cousin the 4R's) that bear checking out before a total rebuild... Note that the 5R55E can be diagnosed somewhat by running the computer codes - which store information about the shift qualitiy and timing of the tranny.

1. The valve body bolts tend to be loose - a retorque with a quality inch-pound torque wrench to factory specs with the factory torque pattern often works wonders for shift quality.

2. Becsuase the valve body bolts work loose (or are loose) the valve body plate gasket is prone to blowing - the valve body needs to be dropped to inspect for this - an easy fix and one that does not require removing the transmission from the vehicle.

3. The electronic control solenoids can work out of their bores due to hydraulic pressure and weak retaining straps. This is fairly common - and the fix is to replace the straps with newer, heavy duty versions.

4. The EPC solenoid can fail due to contamination - and it can be replaced easily without pulling the entire transmission.

5. After the easy stuff, there are other internal issues - front overdrive sprag frozen - affects shifting becasue this transmission shifts into and out of overdrive to "split gears" from 3 planetary sets to 5 speeds. The intermediate band tends to wear rapidly - and the o-ring seal in the acuator bore is prone to damage from the heat of the nearby cat converter. Major drivability issues stem from a faulty torque converter seating.

This transmission is somewhat "fussy" to rebuild - and parts are expensive. While it can be done at home, it will take someone with the correct tools - and the willingness to measure parts and replace what is needed. There seems to be virtually no tolerance for sticking parts or mis-fit parts. Ask me how I know... :D

I recommend that people running any of the new tansmissions add cooler capacity in addition to that provided in the stock vehicle - and that you also run an external filter to filter out the fine sediment particles that clog up the small-sized internal passages in the transmission and the solenoid valves.

Hope this helps.

lmao, its a "new age" C3? LOLOLOL

Wheres an XR4Ti when you need one.

The trans cooler thing is true for all auto IMO....especially Fords.

glfredrick - thanks for the info. basically the thing has 100k+ and hes look to drop a couple hundred bucks for a few more years of use, instead of 2k for a rebuild, or 20k for a new car.

GlFrederick, Kudos, that is some damn good tech info!! :smokin:

Thanks for the kudos... I have learned the hard way about those things from having one myself.

glfredrick - thanks for the info. basically the thing has 100k+ and hes look to drop a couple hundred bucks for a few more years of use, instead of 2k for a rebuild, or 20k for a new car.

That isn't likely to happen unless on of the non-internal things are wrong - then you can get by for cheap - and do it yourself in the driveway. Anything internal that needs repair - even if you do it yourself - is going to run into at least $500. Let me know if you want some of the parts I pulled back out of my own failed rebuild attempt... Oh - and don't even TRY to re-use the torque converter. That is guarenteed disaster.

As for getting a used one - well, I'd really be checking the mileage - or looking to see if it has already been rebuilt before I purchaed one used - they are basically all the same (as in they all have the same problems and mileage related issues) and they really sell for a lot of money...

if you dont rebuild trannies frequently they can be a bitch. if theres any metel in the pan then 500 is low for hard parts.


theres a few outfits offering hop up aftermarket stuff now. big big money though.


bottom line on these trannies is your taking the chance of pissing in the wind with a used one.

if the fluid is changed at 30k and every 20 k afterwards from new then they will last a long long time, but thats real bad odds on an explorer..they are almost always leased or dumped by the primary owner after two years and i rearely see it done. plus the primary owners that tow definatly abuse these things as they seemingly tend to be retards from what and how they tow from what i observe them towing with thier new ones. they could care less.


i do not reuse clutched converters ever. when taking a converter and tranny from a doner situation that is non clutched, i may install the original converter with the tranny if theres no metel at all but thats moot with this tranny family cause they are all clutched converters, generally i put a fresh converter in any swap out though, even 350's and c series trannies..

i replace the hard lines and hot flush the tranny cooler and the secondary cooler and replace the rubber hoses connecting them as well. an inline filter is ok, but if you need an inline filter your fucked any way. with 20 k changouts of fluid if there is any reason for an inline filter the pos needs rebuilt.