I have a 1997 E-4WD with 108k miles on it. It has the 5-speed AUTOMATIC transmission in it. I'm pretty sure they were only offered in the '97 AWDs. It works fairly well, but at highway speeds it has a problem. When going up a hill and giving it more throttle (lugging it), it will suddenly start bucking like crazy. I let off the gas and it goes away. It seems to be getting worse. Can anyone shed some light on this? Also, can anyone tell me the history of this tranny? Is it still made? Poor History? Lemon?

 

I can't comment on the problem, but I can answer the history end of the question to an extent.

The 5-speed auto is the 5R-55E, IIRC. Same as in the Explorer/Ranger. The 5R- is a varient of the 4R-55E that replaced the A4LD in '95. The powertrain folks at Ford programmed it use OD with 1st as well as 3rd to give it 5 effective ratios, even though it's a 3 speed with overdrive at heart. As a result, 1st, 2nd and 3rd have odd spacing, its almost like it has a split 1st. They could've gotten trickier still and made it engage with 2nd too to give 6 speeds. They actually did do that with some of the Ranger desert race trucks around '00 or '01, IIRC, but the drivers didn't really like it.

Anyway, this transmission is still in use in the Explorer and Ranger. Its also in the Lincoln LS, the T-Bird, and I think the new Mustang gets it too. So, they're still around. I heard mixed things about them when they were new (in '97), but recent reports make them out to be pretty robust, or at least reliable.

I hope this helps at least some...

 

Thanks for the info. That helps a lot. I think I've figured out the problem part of this post by reading some of the other threads. It sounds like the bucking problem is torque converter clutch slippage. I'm going to try disconnecting the torque converter clutch lock-up solenoid and see what happens. In the other thread I read they did this and the problem disappeared. I won't leave it disconnected, but I'll disconnect it temporarily to isolate the problem. Although, this tranny is not an A4LD (as was used in the other thread) so it may not work the same.

The function of this trans sounds somewhat like the old 4+3 manuals on Corvettes. They had an automatic overdrive stuck to the back of a 4 speed manual. You could get a ratio half way between each gear by turning the OD on and off in between each manual shift. You could get 7 ratios I think.

This is really really weird, but the Ranger race team wasn't the LASD Race team was it? If so, I drove that same truck, with that transmission, for about 100 miles back in 2000 (and wondered what kind of transmission it had at the time). We were testing an Auburn differential.

 

I don't know if LASD's transmission was programmed like that or not. I was working with MacCachren at the time, so that's the only BITD Ranger I had direct experience with. I'd guess, though, that since both were "house" teams supported by the same folks at Ford Racing, they got similar transmission programs...

 

f I had $2000 to play with I would like to add a Gear Venders overdrive to my 4ALD tranny. It bolts to the back of the tranny and you can select OD between every gear turning our 4 speeds into 8 with the 8th being double OD.