Clunk, bump or hard shift at about 35 mph

[cahhtravis4]

Just bought a 2011 Expedition 2 wheel drive xl w 79,000 miles and the 6r80 transmission. About 2 weeks later started experiencing a random clunk, bump or hard shift at 35 mph. Not sure what to call it for sure. Seems to be doing it more and more but not every time we pass through 35 mph. Haven't owned it long enough to know if happening more when going up a grade or not but many of the times that has been the case. Not sure if relevant. Update: Just took it out for drive and figured out that 35 to 40 is the magic spot and it happens when you get to about that speed and then let up on the accelerator and then accelerate again after just letting up. Don't think it happens when you just steadily accelerate through the speeds. But if you have to slow because of traffic and then hit again quickly it happens but not at other speeds so far. Any ideas about what could be going on? Hoping the fix isn't a whole new transmission.

 

[JARR3R]

I'm having this same issue with my 2002 with the 4R100 trans. I have noticed it happens when shifting out of second which i think is around 30mph. Never throws a code or O/D flash.
Things I have done.
Tranny service from trans shop said it looked fine.
New spark plugs. Ouch that hurt.
Cleaned mass air flow.
New throttle position sensor.
Still have the problem. I think there might be a TSB on This issue but I have not got it to the shop yet.

 

[Mediamonkey11]

I've noticed this similar issue on my '00 EB, and my '08 E150 both with the 4r100, or what seems to be this issue. It'll be when accelerating and let off the gas after shift into OD, then beginning to accelerate again it will hesitate slightly and give a nudge as it drops what I think is 2 gears into 3rd. I think it's a threshold shift that it can't decide if 3rd or 4th would be best and can't make the shift well? If memory serves this has been tlaked about multiple times before over the years with no issue pointed other than a qwerk of these trannys. I would however take it to a shop to get the trans serviced or do it yourself seeing as it's a new vehicle to you, either way....

 

[cahhtravis4]

Thank you Jarr and Tony for the reply. I was loosely finding the same answer out there. Just a glitch that doesn't seem to be a problem. Thanks for the reassurance. This Expedition has the 6R80 transmission.

 

[jonxbk]

Hello, I have a 2015 Expedition 3.5 eco and 6 speed tranny. I have been experiencing this same slight clunk/knock sound when driving 30-40 mph. It happens almost everytime it upshifts from 4th to 5th gear on city driving. I don't feel it on the freeway. And there are times i hear a clunk from getting off from a stop or when slowing down to make a turn and accelerating afterwards.

The clunk is not noticeable when you have the radio on. At first I thought I was just hitting bumps and it would make that sound.

Its been driving me nuts for weeks now. Went to a ford dealer, they did an update on the PCM but the problem still persists.

I got an appointment tomorrow to have the transmission fluid changed.

Still not sure if its a tranny or axle or U-joint issue or maybe it's normal????

Please help. Thanks

 

[1955moose]

Jon, start a new post. This ones 3 1/2 years old. Most if not all the originals are gone!

Sent from my N9131 using Tapatalk

 

[jonxbk]

will do. Thanks!