P1740 TCC O/D solenoid performance

[ABorgardt]

Truck decided to throw a P1740 code about a week and a half ago. I reset it and went on my way figuring if it was something it would come back. Well, yesterday it came back. According to the service manual there are several possible causes including a faulty solenoid. Im wondering if anyone else has had this code and if it was this simple?



It has been acting a little fun lately, however. I drive in tow/haul nearly all the time and it seems to slip out of lockup in 3rd every once in a while. If i cycle the tow/hall switch it will go back to lock-up.



Please tell me its not the overdrive clutch or the torque converter. I Just had the front band and drum replaced along with an upgraded VB and a shift kit.



Any ideas?

 

[ABorgardt]

nobody has any ideas?

 

[cerberusiam]

Either a connection issue or a solenoid going bad. The ECU monitors the solenoid for resistance between 5 ohms and 100 ohms. When it goes out of those parameters it sets the MIL.



The FSM gives a test sequence to find the problem if you want to go thru the steps. However, an intermittent problem like that will be a bugger to find. Since you had parts of the trans apart I would start with a thorough cleaning of all the connections with contact cleaner and see if that helps.



Woops, wrong thread for having it apart. Still clean contacts first and go from there.



Good luck.

 

[ABorgardt]

clean the contacts on what? the tcc solenoid?. Where is it? The trans was just apart. I had Matt Gilmore fix it about a month or so ago. Needed a new front band and drum. While he had it apart i went ahead and upgraded the VB and a shift kit.

 

[cerberusiam]

The trans control plug, round plug drivers side of trans about the middle of trans. Thats the connection point for all the solenoids and internals. A little dirt, grease, etc, and the contact could be not good. Clean it with contact cleaner and make sure it is seated tightly.



The FSM shows test routines for the harness all the way back to the ECU. Might as well start with the easy stuff.

 

[sweeda]

I agree start with the easy stuff. They worked on it! THEY sould fix it! if its the installed part call your supplier of those parts. changing the VB without changing the Torque Converter could be why this code is comming up. My guess its the VB that is causing it the psi dosn't match the ECM's paramaters. thus a code light is lite. check with the shop or the manuf. to determine if it's a thing that needs atten. a. s. s. p.

 

[WoodJ]

I have a 2005 with a triple clutch convertor and VB. After the install I got the 1740 code and about every 1500 miles or so it will come on. The trany shifts and works great, but have had the code about 15 times in the last 2 years. I have spent alot of time and talked to alot of people about this problem. I have found that it is common on the 48RE to have this code in stock form and very common with any mods. It has to do with the paramaters that are set by the computer. Like clock work my light comes on when the convetor unlocks, the truck is always at light to no throtle at about 45 mph. Of coure there could be another problem, but this is what I have found and no one can find a way to fix my problem. Good luck!

 

[cerberusiam]

I have a 2005 with a triple clutch convertor and VB. After the install I got the 1740 code and about every 1500 miles or so it will come on. The trany shifts and works great, but have had the code about 15 times in the last 2 years. I have spent alot of time and talked to alot of people about this problem.

I would say it is uncommon to have this code stock unless there is an issue somewhere. With a tighter TC it will frequently come up due to the lack of an rpm drop on lockup. The ECU thinks that lockup did not happen due to the parameters in the monitoring software. With a stock TC that really should not be a factor.



Since he said it was occasionally unlocking going down the road and cycling the TH button helped I would suspect an electrical problem or solenoid.

 

[ABorgardt]

Since he said it was occasionally unlocking going down the road and cycling the TH button helped I would suspect an electrical problem or solenoid.

That is the exact reason why i was thinking the solenoid. Any idea where it is and how much the solenoid costs?

 

[cerberusiam]

That is the exact reason why i was thinking the solenoid. Any idea where it is and how much the solenoid costs?

Its on the valve body. Need to drop the VB to change it I think.



Here is th epiece and a link. A500 A518 A618 42RE 46RE 47RE 48RE Transmission overdrive & lockup solenoid,TransmissionpartsUSA.com

 

[ABorgardt]

Thanks for the link... that not a bad price at all, actually a little surprised. So, I have never had the VB out before. Do i have to worry about any springs or anything coming out,or is everything self-contained?

 

[cerberusiam]

There is one spring and piston, the accumulator piston, that will fall out when you drop the VB. The rest is contained in the VB. Might as well put one of these in or a shift kit to fix the circulation in park issue.



Sonnax Transmission, Torque Converter, Performance, Driveline Parts :: Transmission Specialties® :: 22771-09 :: Part Summary

 

[ABorgardt]

I had a new VB and a shift kit put in it when i had it fixed. would any shift kit fix it or just certain ones? do i need to call my guy?

 

[cerberusiam]

I had a new VB and a shift kit put in it when i had it fixed. would any shift kit fix it or just certain ones? do i need to call my guy?

Verify with your trans guy first, it probably already contains all the fixes needed.