Is this normal?

[Bfox111]

When i command the tcc solenoid to off while the truck is running it sounds like bearings dragging and grinding from the torque converter. Has anyone else experienced this?

Allison 6 speed

 

[Mike L.]

Explane exactly what you're doing. I didn't understand any of what you are try to say.

 

[Bfox111]

Sorry Mike. Im using efi live to control the shift solenoids in the allison to test weather or not i can hear them engaging. While the truck was running, i commanded the TCC solenoid to turn off. When i did this i can hear noise from the torque converter that sounds like bearings grinding. Is there a problem witht the torque converter or is this normal when this solenoid is commanded off? Thanks in advance

 

[Mike L.]

If you are standing still the solenoid is off.

 

[duratothemax]

Im confused why you need to command the shift solenoids on and off to see if they are working...what are you trying to do???

If the solenoid is commanded and the valve doesnt stroke (IE, the PSM doesnt see a change in pressure), the TCM will set a code. So if there arent any codes, the shift solenoids are working properly.......

 

[duratothemax]

If you are standing still the solenoid is off.

Although in park/neutral with the truck standing still, the solenoid can be commanded and the TC can be locked (neutral lockup for PTO stuff) correct?

With the truck standing still and with neutral lockup commanded, you will hear a slight rattle...but it should not be that loud...the rattle should go away when the TC is unlocked in park/neutral. (f-trim solenoid off)

 

[Bfox111]

I was doing this because i have a p0762 solenoid C stuck open cel. I just wanted to make sure all my solenoids would respond to being commanded on or off to try and eliminate it being a bad solenoid. I was playing with the tcc solenoid and noticed that when it was commanded off (in park) i heard a grinding noise that was coming from the converter. Im just trying to eliminate any problems that might set off this particular cel. My next step is to order the sonnax tool for the e shift valve and a stronger spring to see if i can free this valve from sticking. Ive already disassembled and cleaned the VB numerous times and still cant clear the code. So its time to order the tool... Does anyone know the part # of the e shift valve itself? I may order that too.

 

[x MadMAX DIESEL]

If you try and lock up the TC while in neutral, which I'm guessing is what your doing? They will make a funny grinding noise. Maybe not "they" but atleast mine does, or did last time.