2nd Gen Non-Engine/Transmission do we have controll over torque lock?

[GreggNoble]

hi, i have a habit off cancelling my overdrive and or manually putting my trans in 2nd gear when goin down hills to save brakes ,i am off the understanding that this locks the torque taking the stress off it.

i also do this when towing ,am i right in this understanding?

 

[Tinman]

Nope. The stock 47re is never locked in 2nd. It also won't lock while decelerating (no throttle applied) in 3rd or 4th. A locked tc creates more stress not less. DTT makes a controller for their VB that does have 2nd gear lock up as well as it keeps the tc locked in 3rd and 4th reguardless of throttle position. This dramatically increases engine braking over the stocker.

 

[GreggNoble]

Thanks Tinman for setting me strait there! so that being said i guess i should just make the brakes take the heat and not pull down in 2nd or cancell my overdrive button?

i already have a problem where my torque slips when i hit a bump on the highway,i hope its not from pullin the stick down in 2nd goin down hills!!!

 

[georgej]

Gregg



I always lock out OD when descending hills and it helps a little to keep the speed down when towing our 12000 + lbs. 5th wheel. I do have 4. 10s in the differencial. Have about 130K mi. on the truck about half those miles are towing with no transmission issues. I did upgrade the TQ converter and valve body at about 85k mi. to help get the power to the ground and it was money well spent.



Geo

 

[Tinman]

There's nothing wrong with using 2nd or 3rd to engine brake. It's just that with a stock trans your aren't going to get near the braking effect with the TC unlocked. That's why the 48re has 3rd and 2nd gear lockup and is "approved" for exhaust brake use. If you have a slipping TC, it won't be from using it to slow down on an otherwise stock trans. Engine braking is stressful on the trans with lockup and an exhaust brake. Enough so that I've been told to consider a billet input shaft.

 

[GreggNoble]

should there be an error in my truck if its an external issue thats causing the torque to slip? i checked it on saturday with a superchip handheld and it said no error codes!

 

[SHuber]

A locked TC may create more driveline stress but it does not create more heat, unlocked = heat & heat = problems... Locked up TC is better weather you are on the fuel or off it.

 

[GreggNoble]

shuber, i`d like to understand how that works ,cause i had the conception that i should do what i can especially while towing to keep my torque locked to avoid stress on the torque. some people disagree with this ,i wish i could see a torque disassemble so i could understand what is goin on when the torque is lock vs" unlocked

My trans is totally stock and has 255000. klm`s on it should i ungrade it now to avoid problem in the future?

 

[Tinman]

Heat is the biggest enemy of a trans, no doubt.



My 47re lost a O/D solenoid once, went into limp mode (3rd and 4th only) and no codes.



Like I said, a good trans is the best thing you can do to your truck. Any excuse is good. And if yours is really slipping, then driving it further can cause more problem = more $ later.