2000 F150 xl automatic -- can not go past 40 mph in overdrive
Overdrive button in shifter ..by default it is on but when I drive it when overdrive is on ..it wont go move than 40 mph ...if I try more than 40 mph ..engine just revs and make noise

But if I turn off overdrive by pushing that button ..it will go more than 40 mph ...but I feel it's making more noise than normally it should (may be its just in my head)

What is the reason for this ? and what is the fix?

I have been told ...changing transmission fluid with filter and adding lucas transmission fix would fix that..is that true?
Or its something inside the transmission?

 

Ok, it sounds like you are saying the transmission free revs when it's either trying to make the shift into 3rd or overdrive. That could be a couple of things,

Can you drive it at 40 with the overdrive off and tell us how many rpm's the engine is turning at that speed?

D

 

Sounds like this to me:

https://www.f150online.com/forums/tr...roke-pics.html

Not a fluid issue.

 

If I disable OD by pushing OD button truck will go over 40 mph. (but without disabling OD it will just rev as if its in neutral)
I removed transmission pan and removed valve body and I found that snap ring on reverse was broken..and few pieces were in the grooves of valve body ( I dont remember where exactly they were) ..overdrive servo (snap ring) was not broken...
Do you think this broken reverse snap ring(servo) is the reason why ...it wont go pass 40 mph unless OD is disabled?
I replaced 1-2 and 2-3 accumulator and piston and that broken reverse snap ring but have not touched overdrive section.
Do you think I should remove overdrive snap ring and check if spring inside is ok?

 

You should get your transmission rebuilt. You don't want pieces of metal floating around.

 

I already removed those broken pieces ...what else could be reason why overdrive is not working?

 

Answer Darrin's questions if you want help.

 

Yes I can drive if I disable OD by pushing that button ...and I dont remember rpm at that speed and I cant check it now because bottom is apart.

 

Yes I can drive if I disable OD by pushing that button ...and I dont remember rpm at that speed and I cant check it now because bottom is apart.