95 f150 tranny shudder diagnosis help

95 5.0 with auto 2wd and 3.08 rear if it matters (no locker or limited slip)

This tranny has a O/D on/off selector on the column lever.

After accelerating up to town speed limits (45) the tranny will shift into and out of OD as it "hunts" for the right gear. Example: Light pedal pressure to maintain 45---going uphill it shifts down---other side of hill it shifts back to OD.

Anyway, when it shifts into and out of OD I get a shudderthumping as if I'd just driven over a forest service road (washboard). This only happens during the shift, not on either side of it.

When I select OD off at the lever it happens much less or not at all.

Any ideas?

Thanks

I think 45 mph is right about at the OD point in the tranny.. so when town driving I'd keep it out of OD... maybe its time for a fluid/filter change and run some cleaner/conditioner throu it... then change it..
Tim

I have a 1990 f-150 4x4 with the 5.8 and e4od. Its the same tranny you have and yes it shifts into OD at about 43 mph. Like the other guy said, it probably needs a full system flush on the tranny and depending on the mileage your pressure plates may be worn out, but those aren't cheap to replace. Get a tranny flush and filter change and let use know if there is any improvement. ...... And keep er outa OD in town.

Scooba_guy

Thanks guys. I'll do it and probably chuck a bottle of lucas in there just to see.

Tom

Might I suggest something?

Go buy a pint of "Trans X" You can find it at many parts stores.

Drop that in your tranny and drive it for an hour or 45 minutes normally.

Then go home and let it idle for about 10 minutes, and then change your fluid.

That Tranx X is the BEST varnish remover I've ever used, and it will bring a tranny back from the edge if used correctly! I recommend it to all my cutomers with tranny problems, and even those without that don't change their fluid every 2 years.

I use it in my vehicles about 1 week before each tranny fluid change every two years.

If you can't find a shop that will change all 14 quarts of tranny fluid on their machine then just do the regular old drop the pan & filter, and go that route.
But do it twice.
Do it again after a half hour of driving so you can get at the other 8 quarts you weren't able to drain from the system by only removing the pan.
It really helps to dillute the old crappy fluid with the new.... You'll not get all the old crap out without goint to a shop that does a tranny flush.

The generally run less than $90 bucks. Even here in Norcal.


FE