Have Transmission Questions? Ask a Mechanic for Answers ASAP
Hello my name is ***** ***** thank you for your question.
What codes are you exactly getting now?
If it is throwing no codes, then you have a mechanical issue causing your problem. Not electrical. So you have a internal issue with in the transmission which will eventually require transmission repair or replacement.
I worry more with no codes. At least if there was codes, it could possibly be solenoid or a Valve body. But when there is no codes, that means it's a mechanical issue I am afraid.
Well the steps would be to do line pressure tests. Stall tests, then drop the valve body and do air checks for each gear to see which gear is causing the loss of pressure for overdrive
This way, when you take the transmission out, you know what area to inspect for your exact issue.
No.. Not at all.
I know what you meant. No a APP sensor will not keep overdrive from operating. If you had a issue with the APP sensor, you would certainly have codes.
That is for the low coast solenoid valve. That is electrically controlled by the TCM. If your not getting that code any more, the flush may have cleared out any debris that may have been in the solenoid.
How many miles on the truck?
You flushed the transmission with that many miles?
So that is around 139k miles. You should never flush a transmission with over 100k miles. That could do internal damage if the transmission has not been serviced properly
Hello my name is ***** ***** I can help you. I have reviewed your previous talks with Jay. From the last statement about the tranny fluid looking like a mud puddle, there is a very high chance the radiator went out before you bought it and contaminated the trans fluid. This is a common issue with the mileage you have. Once that happens you can kiss the valve body goodbye and most of the time the trans as well. My recommendation would be to find another trans with lower mileage. We use LKQ.com at our dealership and have had good luck. If you have any questions feel free to ask!
The problem is that the TCM is a part of the valve body. Once coolant is introduced it somehow damages either the valve body or the TCM. I have seen the TCM short out and take out the entire BUS network until you unplug it. You can replace the valve body, however, you need to check the price of a valve body vs. a entire trans assy. If you do just replace the valve body, keep in mind you will have to have it programmed at the dealer. The cost should be 1.5hrs to replace valve body + .5hr to program TCM. Plus addition of more fluid to refill the trans. If the valve body still doesn't fix the issue, then the trans will have to be disassembled and a possible replacement of the overdrive clutches will be necessary. It is a tuff decision I know. However, if you just replace the trans, you stand a better chance of illuminating comebacks. Replacing just the valve body is rolling the dice, most of the time you will lose. I have tried replacing the valve body only to have to put a trans into it later cause the issue didn't get fixed.
If you drive it with the overdrive off you will not only damage the trans further but make your engine work at higher rpms. If you are trying a temporary fix you can go to autozone and buy some Lucus trans additive. Maybe it will help fix the issue for now. You may have a valve sticking somewhere not applying enough pressure to the friction clutches. It is worth a shot!
I am logging off for now but will be back on tomorrow.