exhaust brake problem

[RDBrown]

My "08 Ram 6. 7 automatic transmission will not go into tow/haul (no rpm bum) when engaged. Also the exhaust brake disengages at around 42 mph with tow/haul. I do not have any exhaust brake below 42 mph. You can toggle the paddle shift down through the gears and exhaust brake will work down to 1st gear. Has anyone had this problem, and if so what was the fix? I had it at a dealership and they called the tech line, but no solution. Thanks Ron

 

[Newt]

On my 09, the exhaust brake disengages at ~1,000 RPM. It is based on RPM, not speed. If you want it to work at lower speeds, shift down.

Newt

 

[HBarlow]

My "08 Ram 6. 7 automatic transmission will not go into tow/haul (no rpm bum) when engaged. Also the exhaust brake disengages at around 42 mph with tow/haul. I do not have any exhaust brake below 42 mph. You can toggle the paddle shift down through the gears and exhaust brake will work down to 1st gear. Has anyone had this problem, and if so what was the fix? I had it at a dealership and they called the tech line, but no solution. Thanks Ron

If "rpm bum" means rpm increase when you activate Tow/Haul mode that's normal on a pickup. Tow/Haul mode changes shift points accelerating and decelerating but does not change gear ranges. You can do that with the button on the shifter handle.

Your truck probably has 3. 42 gears if the exhaust brake function is deactivated at 42. That's another of many disadvantages of that gear choice. You can overcome it with downshifting.

 

[RDBrown]

The truck has 3. 73 gears. it worked before the last time it was at the dealership. When in tow/haul the torque converter would unlock and RPM's went up about 2-300 rpm's and as long as the tow /haul was engaged I had enhause brake almost down to a stop.

 

[Cummins12V98]

If "rpm bum" means rpm increase when you activate Tow/Haul mode that's normal on a pickup. Tow/Haul mode changes shift points accelerating and decelerating but does not change gear ranges. You can do that with the button on the shifter handle.

Your truck probably has 3. 42 gears if the exhaust brake function is deactivated at 42. That's another of many disadvantages of that gear choice. You can overcome it with downshifting.

When slowing down without using brakes mine usually kicks out at 30. I have 3:42. If slowing fast with brakes it will go to 20 before kicking out.

 

[HBarlow]

The truck has 3. 73 gears. it worked before the last time it was at the dealership. When in tow/haul the torque converter would unlock and RPM's went up about 2-300 rpm's and as long as the tow /haul was engaged I had enhause brake almost down to a stop.

I think you're misunderstanding what is happening. The torque converter would not be unlocked during deceleration when exhaust braking is activated or internal slippage and overheating of transmission fluid would be the immediate result.