Transmission control solenoid

[Jason1987]

Hi, I think my transmission control solenoid is going. After driving for a little bit the service light comes on then shifts hard. Has anyone had this replaced? From what I have researched there is a solenoid for each gear. Does one get replaced or all usually? Also if anyone got it done how much was it? My mechanic doesn't want to touch it and suggested I go to a transmission shop. Any help/advice would be appreciated. Thanks in advance.

[lrbraner]

Originally Posted by Jason1987

Hi, I think my transmission control solenoid is going. After driving for a little bit the service light comes on then shifts hard. Has anyone had this replaced? From what I have researched there is a solenoid for each gear. Does one get replaced or all usually? Also if anyone got it done how much was it? My mechanic doesn't want to touch it and suggested I go to a transmission shop. Any help/advice would be appreciated. Thanks in advance.

Been there, done that. It is the pressure control solenoid. Some members have successfully replaced it themselves. It is a PIA.
I couldnt find a trans shop that would replace only the solenoid.
They all wanted to do a complete rebuild.
So $1400 later it is fixed.

[02 LW300]

The solenoids are difficult to access, the are under the end cover not in the pan. Four speed automatics usually use three solenoids, one variable to control the line pressure an two on and off to make up the four gears. You have to lower the cradle and lower the transmission to get the cover off for access.

[floridasl22002]

Jason,
I've done that job on my son's 2003 L300. Here's the link to the job;
http://www.saturnfans.com/forums/sho...d.php?t=235496

When I did the job, my son left the car with me so I was not under the gun to get it done by a given date/time. It is a PITA job, but the tranny shop I took it to for the hard shifting only wanted to replace the tranny and relieve me of $2000.00. Given I only paid $2100.00 for the car, that was never going to happen. Doing it myself costs me just a couple of hundred dollars and the tranny has been fault free since. I think I did the job over 2 weekends, taking it steady as I'm no spring chicken.

Because you have to lower the sub frame on the drivers side to allow access to the tranny end housing where the solenoids are, you have to loosen the sub-frame bolts. The car started life as a northenr car, so I was concerned about the bolts coming out. I had the car in the indi shop I use for jobs I can't do and asked the mechanic if he could try and loosen the bolts, then tighten them back up for me. That worked and was a great help in doing the job.

One thing the tranny shop did tell me when I asked how long can we drive the car with the hard shifting was that if you are doing short round town trips, it could be fine for years. If you did long journeys a lot, then all that would happen would be the tranny would go in limp mode and force you to fix the issue. The tranny will not self-destruct as it will protect itself from damage.

[Jason1987]

Thanks everyone. Maybe its time for a new car but it only has 85,000 miles. Does anyone know if this usually happens when its hot out? I drive it occasionally in the summer but its my winter car and drive it more then. So if its less likely to happen in cold then I may be ok. I live in Massachusetts.

[floridasl22002]

Couldn't answer that. Others who have the issue have been in various states, so I don't think it's external heat related. One of the things I can tell you is that I watched a youtube video of a CA who strips down transmissions and then rebuilds them. He did one video of the tranny that's in the Satty and other GM cars. He said that where the solenoids are located, one of them sits above where the normal tranny fluid level is and so doesn't get the same washing of fluid as the others do. He said as a result, it gets hotter. That can't be good in the longer term. With 85K on the clock, if the rest of the car is in good condition, then having a go at replacing them yourself could be a money saving/car saving project.

A tranny shop would charge you a good chunk of labor to replace the solenoids IF they were even prepared to do the job. If you're not able or comfortable doing the job yourself, maybe seek out a mobile mechanic, who could do it cheaper for you.

If you tried to sell it, then any selling price would reflect that issue, so you wouldn't get much for it.

[fdryer]

Originally Posted by Jason1987

Thanks everyone. Maybe its time for a new car but it only has 85,000 miles. Does anyone know if this usually happens when its hot out? I drive it occasionally in the summer but its my winter car and drive it more then. So if its less likely to happen in cold then I may be ok. I live in Massachusetts.

I drive longer distances in winter, to reach a local ski area in NJ. From home to ski area is about 60 miles each way. Occasionally, the wrench light turns on about 2/3rds of the way and shifts harden. Mine started to occur around 75k/85k miles. Never occurred in summer but I don't drive as far or stop along the way on long drives. Back then I noticed after stopping at my destination and coming back hours later, the wrench light resets and shifts were normal for the entire drive home. I learned to stop as soon as the wrench light/hard shifts occur, let the engine/xmission cool down for about 10-15 minutes then continue with the wrench light resetting and shifts returning to normal. Anticipating this almost every time on the same route, I stop by someplace for a quick breakfast and drink, long enough time for the xmission to cool down and not have the wrench light/hard shifts occur. Same route thru local streets, bridge, highways and state roads.

Service manual descriptions for P1811 Maximum Adapt and Long Shift or similar error codes describes an issue when a xmission error occurs and the tcm protects the xmission by defaulting to high pressure shifts preventing damage to shift clutches. Electronically controlled xmissions use pulse width modulation to vary power to pressure control solenoids to move them into various positions to modulate hydraulic pressures. Each pcs doesn't operate on or off but vary plunger position by pulsing the solenoid to vary pressures for smoother shifts. I drained xmission oil, replaced filter and refilled with xmission oil around 100k miles in hopes of this problem going away. Not.

I'm at 115k miles and haven't changed the pcs. The hard shift just occurred in warm weather so I simply stop for a drink, rest room break, maybe open my tablet and surf the internet to pass the time before continuing my drive somewhere. Wrench light resets/hard shifts reset. I think these solenoids break down electrically and have nothing to do with xmission heat.

Be aware of major maintenance coming up. At 100k miles, the timing belt, idler pulleys, water pump and spark plugs are due for replacement to ensure long term reliability. Whether the water pump leaks or not, it's wise to adhere to service manual recommendations because many parts are removed before having access to the timing belt and water pump so it's simply wise to replace the pump instead of taking a chance and revisiting to replace the pump if only the timing belt was replaced. This can be costly by dealer or repair shop. Plugs last 100k miles (platinum) so this is the best time to replace them too.

Several upper engine parts are removed before access to plugs. Several threads of members performing these procedures, some with snapshots and not using the timing belt kit to restrain camshaft movement during belt replacement.