Hey guys. I'm helping my brother work on his truck - hoping to save us some money if we can. The truck is a '90 F-150 with the 300/E4OD, 2wd. Let me lay out what's going on:

Ever since we got the truck, we've had an issue with the 2-3 shift. It shifts 1-2 smooth as silk, and 3rd to OD is smooth too, but 2-3 SLAMS the crap out of you. He's been getting by so far by anticipating the shift and quickly letting off the gas. The trans will shift into third gear just fine. We've checked all pertinent fuses and they are fine.

We do NOT have a blinking OD light (though I'm not necessarily sure where it would blink on these trucks - I assume the indicator light under the button?). The only code from the computer is an EGR code, and I know the valve's no good and needs replaced. We don't have a bouncing speedo, or anything that would necessarily cause me to condemn the VSS outright.

Now, this truck likely has over 200K miles on it, and it lived most of its life as a farm truck, so I'm certain maintenance was lacking. The transmission leaks, whether its the TC or the input shaft seal I'm not sure but it's coming from the bellhousing and leaks enough that you can see it's red ATF. They quit running it because they got tired of refilling ATF all the time. Did they run it low and cause problems in the past? I don't know. Trans has to come out anyway to get this leak fixed; BUT I don't know if these symptoms are being caused by the sensors that control the transmission or whether the PO (or any employees) hurt something mechanical inside the transmission. We haven't done a fluid flush and looked in the pan, only because it would be a waste of ATF since it's all going to evacuate sooner or later (the leak is getting to the moderately concerning level).

I'd appreciate anyone's insight on this. I can test any pertinent sensors to try to rule out electrical gremlins, I just need a little guidance on what I'm looking for. I know these E4ODs can act a fool if the computer isn't receiving the proper data to make them shift right, and the last thing I want to do is tell my parents the trans needs to be replaced, only to have it do the same thing on a brand new trans.

 

Read this short thread created a few days ago. https://www.ford-trucks.com/forums/1...ed-spring.html

 

Yep, I would say check the accumulator body for a broken spring or a jammed valve. Right in the front after the pan off.

Dealt with this on a Mercedes 722.3 once, same thing. Broken spring jammed the valve in the valve body. Easy fix.

 

Huh. Interesting. Definitely gonna check that out.

I know we ought to have pulled the pan first, but like I mentioned before all of us had kind of written off the trans as being no good. Will let you all know what we come up with.

 

Try unplugging this rabs behind the glove box. It worked for me a couple yrs ago. I had bouncing needle tho too, but its worth a try.

 

It surely is worth a try - that's a nice easy test. We'll try that.