7Dave
Junior Member
Hey all, forgive me if there's information on this subject somewhere already, I searched but if you search "engine" and "braking" or "compression" it tends to bring up about 8 trillion posts on unrelated topics.
My issue is this: I have a 2019 Ram, 5.7, ridiculously tall gears (3.21s I believe), and the thing doesn't engine brake worth a darn. I understand the gears are tall, so in some situations, like driving down the face of the mountains I live near, lower gears may help. However, in my feeble brain, my mechanical sense tells me that lower gears won't really change engine braking much when I can already downshift the transmission to the point where it's at high RPM, which means the effective ratio is already low enough. Lower gears would only change the transmission gear I might need to be in to achieve a certain RPM, they won't change the amount of force the engine can physically exert on the drivetrain to slow the vehicle. (input on this logic, or maybe lack thereof, is welcome)
I have another situation though that has been quite peculiar as well. When driving on trails in 4 Low, attempting to use the engine to control a descent, the truck will "modulate" my speed. Even on trails that aren't very steep, it will rapidly speed up, RPMs might go to 3,500-4,500, and then the truck will do...something...and it will slow back down to maybe 2,000 RPM (with zero throttle or brake input from me). It's pretty bizarre, I've never had a truck act this way. I can't decide if it seems that the torque converter is doing something (locking or unlocking? do these converters have a lockup function like the old ones?), or if it's a throttle control issue. It almost seems like it's the throttle opening itself, as when it starts to speed up like that, if I don't want it to be at 5 grand singing like it's going to explode, I'll apply brakes, and it feels like I'm fighting the truck, like it doesn't want to slow down. I've also noted that sometimes in hi range, the truck will drive itself up slight inclines, as if it's holding the throttle slightly open. Apparently it has a mind of its own. Anyone else notice strange things like this, or have I lost my mind at a younger age than previously thought possible?
Thanks guys!
My issue is this: I have a 2019 Ram, 5.7, ridiculously tall gears (3.21s I believe), and the thing doesn't engine brake worth a darn. I understand the gears are tall, so in some situations, like driving down the face of the mountains I live near, lower gears may help. However, in my feeble brain, my mechanical sense tells me that lower gears won't really change engine braking much when I can already downshift the transmission to the point where it's at high RPM, which means the effective ratio is already low enough. Lower gears would only change the transmission gear I might need to be in to achieve a certain RPM, they won't change the amount of force the engine can physically exert on the drivetrain to slow the vehicle. (input on this logic, or maybe lack thereof, is welcome)
I have another situation though that has been quite peculiar as well. When driving on trails in 4 Low, attempting to use the engine to control a descent, the truck will "modulate" my speed. Even on trails that aren't very steep, it will rapidly speed up, RPMs might go to 3,500-4,500, and then the truck will do...something...and it will slow back down to maybe 2,000 RPM (with zero throttle or brake input from me). It's pretty bizarre, I've never had a truck act this way. I can't decide if it seems that the torque converter is doing something (locking or unlocking? do these converters have a lockup function like the old ones?), or if it's a throttle control issue. It almost seems like it's the throttle opening itself, as when it starts to speed up like that, if I don't want it to be at 5 grand singing like it's going to explode, I'll apply brakes, and it feels like I'm fighting the truck, like it doesn't want to slow down. I've also noted that sometimes in hi range, the truck will drive itself up slight inclines, as if it's holding the throttle slightly open. Apparently it has a mind of its own. Anyone else notice strange things like this, or have I lost my mind at a younger age than previously thought possible?
Thanks guys!
