4.0 automatic problems

[ieatcamaros]

The truck I have is a 2000 4.0 auto 2wd. I think I have the 4R55E trans since it is a 4 speed. I have consulted the Haynes, but I am sure you know where that got me.

The problem is very intermittent. When cruising between 45mph and 50mph, the truck jerks hard for a split second. Almost like getting hit from behind by another car. I noticed that when accelerating, the truck shifts about that speed. That is depending upon how hard it is accelerating, of course It has done this a total of about 5 times in the last three weeks. I drive about 200-250 miles per week. This truck does have 163K on it and I have only owned it since November.
So just yesterday I was driving home and I turned off one street which I was driving about 40 before slowing down to turn left onto another street which the speed limit is 35. Anyway, I don't know what gear the trans was in, but when I went to accelerate(not hard) the trans stayed in whatever gear it was in. It was at least third but I think it was in OD because it was lame acceleration compared to normal. When it did this, I pushed harder on the accelerator and then it downshifted like it is supposed to. So this has got me thinking that these two issues are related and whatever controls shifting on this transmission is at fault. Can someone tell me what controls the shifting on this trans? Or if you think it is something else, I am open to suggestion.

The best I can tell this truck has a lockup torque converter. Right? I don't know too much about automatic transmissions but I do know that the older ones used a modulator valve to shift and these new ones don't. I am more of a manual transmission type of guy (just for reasons like this), but I just could not pass up the deal on this truck.

**Edit** The "TR" code on my door jamb is D.

 

[Wicked_Sludge]

the tranny in your truck is entirely electronically controlled.

how does the fluid look? dark, burnt smelling?

 

[ieatcamaros]

OOPS, I forgot to mention about the fluid. The fluid is not too dark and doesn't smell burnt. It still has a red tint to it, but it does have some brown discoloring. My understanding is that it the fluid is about two-three years old.

 

[Ozwynn]

get ready to buy a new transmission. you could try getting it pressure flushed and change the filter but your trans is on its way out. somebody got it hot. My B2 did that jerking thing once and 2 months later the trans only had 1 gear. good luck

 

[ieatcamaros]

BDAB, what was your situation like in your bronco? Did it have the A4LD? I have that thought of buying a new transmission planted in the back of my mind, but I would at least like to try to check the electrical parts first.

 

[Ozwynn]

the electronic parts don't matter much. an automaic is an automatic and it is still fluid driven and uses clutches and bands. if you have the budget check out raptor transmissions........

 

[exbass94]

I wouldn't be so quick to write this off as a blown tranny yet. It sounds a lot like the shift flare that is a common problem with these trannies. It's caused by a faulty modulator or some other electronic gizmo on the tranny. The Ranger I drive at work will practically give you whiplash when it shifts from 2 to 3, but it's been doing this for well over 6,000 miles and it hasn't gotten any worse.

 

[ieatcamaros]

From what I gathered on the explorer site, the 2-3 shift flare is more like a slip than a jerk. But I could be wrong. I have also found that the trans code D that I have is for the 5R55E tranny. Thanks for the replies.