5R55S slipping issue
#21
Just had to replace my transmission at 116k miles, around 80k of that was boosted. It had randomly started popping out of gear when coasting, like it was in neutral, and when you got back on the gas it would rev really high and then violently clunk into gear. The culprit? It was the placement of my JDM catch can - water (rain and wash) was getting in the vent on top. Had more than a quart of water in the PA deep pan and my Amsoil fluid looked like a strawberry milkshake. Needless to say I relocated the can from the firewall to the strut tower and made a little shield for the vent when I installed the Super Streetfighter and new PI converter.
#22
The can was installed fairly close to the battery box on the firewall, and maybe if it was positioned a 1/2" inch or so different either way it wouldn't have happened, who knows. This spring I am going to try to somehow adapt a hose or something to the vent and point it downwards.
Last edited by jpplaw; 11-19-2014 at 05:38 AM.
#23
So for you guys with the stock auto tranny and FI, what is the cost difference between replacing the 555 and replacing it with a 4r70w? The guys that switch don't seem to have issues with the 4r70w tranny. Just wondering.
#24
A built 4R70W swap w/ DS, Controller & Converter is about 2-3 grand more than a built 5R55S. Plus you have to "massage" the tunnel and cut up the console for a new shifter.
If it was strictly a track car I probably would have gone that route.
If it was strictly a track car I probably would have gone that route.
#25
Mine is not strictly a track car, but I would race more often if my tranny and clutch were in good enough shape to go. I'm still on the OEM tranny. I'll be replacing it hopefully this spring with a built 4r70.
I leave a lot on the table at the track without the auto.
I leave a lot on the table at the track without the auto.
#26
It's a Thermal (transmission) cooler bypass valve/switch. Basically a thermostat that prevents fluid from flowing to the tranny cooler when the fluid temp is under 170F. Problem is, it is prone to failure (sticking or not opening at all) and overheating the transmission. The easy fix is you put the larger spring that's part of the assembly on the opposite end of the valve, therefore locking it in the 'Open' position.
I've been doing a ton of research since the tranny seems to work well when cold but as it heats up it starts having issues. Valve body and Solenoid packs seem to be 90% the cause of most problems. As long as you catch the problems early enough you avoid burning up the transmission and causing a premature rebuild scenario. If you've got shards in your pan, it's too late, a rebuilt is necessary and I would recommend the Valve body and Solenoid pack be rebuilt/replaced as well since they probably caused the problem in the first place.
I've got 66K on mine and I'm the original owner. I plan on dropping the pan sometime in the next couple of weeks to replace both items.
I've been doing a ton of research since the tranny seems to work well when cold but as it heats up it starts having issues. Valve body and Solenoid packs seem to be 90% the cause of most problems. As long as you catch the problems early enough you avoid burning up the transmission and causing a premature rebuild scenario. If you've got shards in your pan, it's too late, a rebuilt is necessary and I would recommend the Valve body and Solenoid pack be rebuilt/replaced as well since they probably caused the problem in the first place.
I've got 66K on mine and I'm the original owner. I plan on dropping the pan sometime in the next couple of weeks to replace both items.
Where is the thermal bypass switch and if I need to drop the pan would it be advantagous to get an one of the mentioned aftermarket valve bodies? I had the fluid changed about 4K miles ago, dropped the pan and changed the filter. I'm a little leary about getting a flush with 98K on the trans.
Does this trans will go into OD in both 4th and 5th?
#27
Although I never observed it actually happening, water must have been coming in at the back of the hood somehow. The vent is the only place water could get in to the trans, and the dipstick seals up good. Can actually had some water in it when we took it off. I am kind of hoping it wasn't just collecting condensation inside when cooling off overnight, but it seems like too much water to have been just that.
The can was installed fairly close to the battery box on the firewall, and maybe if it was positioned a 1/2" inch or so different either way it wouldn't have happened, who knows. This spring I am going to try to somehow adapt a hose or something to the vent and point it downwards.
The can was installed fairly close to the battery box on the firewall, and maybe if it was positioned a 1/2" inch or so different either way it wouldn't have happened, who knows. This spring I am going to try to somehow adapt a hose or something to the vent and point it downwards.
#28
Once it reaches operating temp it reads 60mph (OD) at 2000 and shifts fine. At the same time I've also noticed I'm getting about 2 mpg worse mileage.
Where is the thermal bypass switch and if I need to drop the pan would it be advantagous to get an one of the mentioned aftermarket valve bodies? I had the fluid changed about 4K miles ago, dropped the pan and changed the filter. I'm a little leary about getting a flush with 98K on the trans.
Does this trans will go into OD in both 4th and 5th?
Where is the thermal bypass switch and if I need to drop the pan would it be advantagous to get an one of the mentioned aftermarket valve bodies? I had the fluid changed about 4K miles ago, dropped the pan and changed the filter. I'm a little leary about getting a flush with 98K on the trans.
Does this trans will go into OD in both 4th and 5th?
The 5R55s will lock up the converter in 4th and 5th gear. 5th gear is OD and always has a locked converter. Your shifts are 1>2, 2>3, 3>4, 4>Lock up, Lock up>5 (OD).
If the thermal bypass was stuck closed, the transmission may overheat the fluid. If it is stuck open, the fluid may never get up to temperature. Deleting the valve will only make getting up to temperature harder to do. Right now, with the PA deep pan (extra 4 quarts) and with extended traffic/highway driving, my trans temperature only gets up to 180* max and then comes back down into the 160's.
#29
By the way, I broke the new TCI transmission in using NAPA Mercon V fluid. I just dropped the pan, changed the filter and filled back up with 8 quarts of AMSOIL (no, I am not a dealer) and it feels like the car picked a couple hundred rwhp back up. Unbelievable difference. The cold temps here must have been thickening up the NAPA fluid.
I am going to change fluid 2 more times with Amsoil and minimize the amount of NAPA stuff left in the trans.
I am going to change fluid 2 more times with Amsoil and minimize the amount of NAPA stuff left in the trans.
#30
09 and 2010 have a different valve body than 08 and below. Some minor changes but, no shop (or website) has been able to tell me why the changes were made or what they affect. They can only tell me that a 09+ valve body will not work in an 08 or older tranny.
Anyways, for the car not holding 5th gear (OD) or dropping out of it you could have Servo bore wear.
The servo's themselves are under the caps marked TCI in this Pic, there's two of them. One for OD and one for 1st/2nd.
This has a pretty good explanation of it and a potential solution. I say potential because 1) the site only talks about the 5R55S in the explorer and 2) it itself says intermediate to long term fix. I'm also not sure on if the servo replacement can be done in-car on a mustang.
http://www.fordservoboretransmission...-solution.html
This below is the permanent fix but requires dropping the tranny.
http://www.sonnax.com/parts/2207
Rather odd if that's the case with an 09 or 2010 but it's not unheard of.
Anyways, for the car not holding 5th gear (OD) or dropping out of it you could have Servo bore wear.
The servo's themselves are under the caps marked TCI in this Pic, there's two of them. One for OD and one for 1st/2nd.
This has a pretty good explanation of it and a potential solution. I say potential because 1) the site only talks about the 5R55S in the explorer and 2) it itself says intermediate to long term fix. I'm also not sure on if the servo replacement can be done in-car on a mustang.
http://www.fordservoboretransmission...-solution.html
This below is the permanent fix but requires dropping the tranny.
http://www.sonnax.com/parts/2207
Rather odd if that's the case with an 09 or 2010 but it's not unheard of.