Transmission Slamming

[flippincgfighter]

The transmission on my 08 keeps slamming in between gears. Its not getting hot, and sometimes it shifts just fine, but lately its been slamming more and more. Its like it gets stuck in between gears.

Ive had to pull over and shut it off and then it kind of corrects itself, could this be a solenoid?

I also saw 300rpms of slip in my tq converter on the spartan 310, so i put it in the 250 and it doesnt slip now. Is it the converter that causes it to get stuck in between gears....or a solenoid? Its done it for a long time now.

Thanks-Gibson

 

[dieseljosh07]

Does it only happen between the 2/3 or 3/5 shifts?

 

[Mark Kovalsky]

Are there codes stored? Has the TOW/HAUL light flashed?

 

[mclean]

add a little trans fluid...mercron lv or sp or whatever the new one is

 

[Mark Kovalsky]

add a little trans fluid...mercron lv or sp or whatever the new one is

Is it low? Or is this just a random add?

 

[09stroker]

DO NOT add more if it's full! Ford over filled mine when they replaced my trans and it caused it to rev-slam and do all sorts of weird things. Drained 6 quarts last week and it runs alot smoother.

 

[dieseljosh07]

If its even 1 quart overfull it will start venting fluid at operating temp.

 

[flippincgfighter]

The slamming is always at about the same speed. Its between 3/5 i would guess. Always right around 25mph.

There is a hill that it always slams on, and i drove it yesterday and manually left it in third gear and it didnt slam.

The trans might be a little full, but not much. I just checked the fluid and it was spot on.

No codes, and the tow-haul button has never flashed.

Im running the spartan 250 early lock.

 

[dieseljosh07]

Might try replacing the direct clutch solenoid, how ever if the solenoid feels tight in the valve body when you try to remove it you may have metal in the valve body or burned clutch material.

 

[powerstrokin15]

the 3/5 shift is pretty hard sometimes, mine used to do it on my KEM files.. are you saying you were getting 300rpm slip with the converter lock?

 

[TripleE44]

A while back I remember others talking about over filling the fluid as well. I know it for a fact that some were saying if you've got this rev/slam its worth a shot. Mine does that same thing sometimes.

Mine actually has stuck in 3rd a few times. Each time I just throw it in 3rd with the selector and get where I'm going. Let it sit while I'm doing whatever it is and when I come back it's fine. Once it threw up a code, but from what I remember it was one unrelated to the trans.

 

[4tonGT40]

The slamming is always at about the same speed. Its between 3/5 i would guess. Always right around 25mph.

There is a hill that it always slams on, and i drove it yesterday and manually left it in third gear and it didnt slam.

The trans might be a little full, but not much. I just checked the fluid and it was spot on.

No codes, and the tow-haul button has never flashed.

Im running the spartan 250 early lock.

Your not gonna want to hear this but my transmission did the exact same thing over and over again. I blamed it on tunes, long story short about a month ago I had our transmission guy build mine with Suncoast ironpac3 , transgo kit, billet input shaft and some other cool schit. Well it hasn't slammed not once. So short answer build your tranny. What the Suncoast kit does is alleviates Drive pressure with a "blowoff" valve in the valve body. And the additional clutches help to I can't say for sure if it's one thing or the other but I can tell u in my case it fixed all that slamming non-sense for good. Let me know if your interested in building one. We do them all in house with Suncoast components. Fully guaranteed of course.

 

[mclean]

mine has done it since new...If i slowly accelerate from a set of lights, half throttle or so, and then let off for a bit, when i hit the go pedel again it free revs until it catches up and then slams into gear.

It seems to be a common problem a couple years ago and the solution was to add a little more fluid, I did and it stopped happening

 

[powerstrokin15]

mine has done it since new...If i slowly accelerate from a set of lights, half throttle or so, and then let off for a bit, when i hit the go pedel again it free revs until it catches up and then slams into gear.

It seems to be a common problem a couple years ago and the solution was to add a little more fluid, I did and it stopped happening

same here

 

[flippincgfighter]

On my way to town today, i slowed down to about 20mph, and it slammed once....let off and touched the throttle and slammed again...let off and touch the throttle and slammed again. The third time it finally caught a gear and shifted from 2nd to 3rd but the little wrench came on in my dash.

Read Codes on my Dashdaq.... P0761: Shift Solenoid "C" Performance/stuck

Once i slowed down to a stop and tried to accelerate it would shift fine from 1st to 2nd, but it will not shift into 3rd, manually or any way. I cleared codes and shut the truck off and it still will not shift out of second.

1st, 2nd and Reverse work fine and the trans isnt getting hot. Im gonna get it to my shop and replace the solenoid....any other ideas??

 

[PSD-BLACK-CLOUD]

Mine was doing something like that. Ford had to rebuild it completly.

 

[flippincgfighter]

That would suck!

This is still running the spartan 250 tune.

 

[Derek@Vision Diesel]

Definitely a solenoid. Factory ford is your only option!

 

[flippincgfighter]

Should i replace all 4 or just the one? Which one is "C"??

 

[flippincgfighter]

Ok i found out there is 7 total solenoids....does anyone know which solenoid "C" is?