eTorque 5.7 and 3.92 limited slip

[DeanKing]

I test drove an eTorque truck with 3.21 gears and 20s. I am not sure if it was limited slip. It was very smooth. The eTorque system was not even noticeable.

I got my truck a few days ago. It has a 3.92 limited slip rear. Other than that, I can't think of what would be involved in the drive train that could affect this. About half the time, the truck lurches with a little burst of torque when I take my foot off the brake at a light. The engine restart is barely noticeable but the lurch forward is unsettling. If I am too quick to step on the gas, it is even worse so I have been training myself to give it a half second but it is still sometimes jumping on it's own before I can even hit the gas. If this was my Mustang, I would be pretty pleased with that. But this is a very smooth luxury truck and it seems kind of uncivilized to be lurching forward. Everything else about the truck is very refined except that.

I am thinking it is either the combo of the eTorque and low gearing or that something is wrong with my eTorque system. Before I go whining to the dealership and asking to test drive a lot of other trucks to compare, I wanted to see if anyone else noticed this.

Does anyone have this combination who could comment? Have you noticed this in yours?

 

[SpeedyV]

I test drove an eTorque truck with 3.21 gears and 20s. I am not sure if it was limited slip. It was very smooth. The eTorque system was not even noticeable.

I got my truck a few days ago. It has a 3.92 limited slip rear. Other than that, I can't think of what would be involved in the drive train that could affect this. About half the time, the truck lurches with a little burst of torque when I take my foot off the brake at a light. The engine restart is barely noticeable but the lurch forward is unsettling. If I am too quick to step on the gas, it is even worse so I have been training myself to give it a half second but it is still sometimes jumping on it's own before I can even hit the gas. If this was my Mustang, I would be pretty pleased with that. But this is a very smooth luxury truck and it seems kind of uncivilized to be lurching forward. Everything else about the truck is very refined except that.

I am thinking it is either the combo of the eTorque and low gearing or that something is wrong with my eTorque system. Before I go whining to the dealership and asking to test drive a lot of other trucks to compare, I wanted to see if anyone else noticed this.

Does anyone have this combination who could comment? Have you noticed this in yours?

I have an eTorque / 3.92 truck, but I also have the ORG (ELocker), air suspension, and basically a heavier truck than yours. I've gotten used to the "golf cart launch", where I simply lift off the brake, wait for the engine to start and the truck to start rolling, and then ease into the gas. If I hit the gas pedal too quickly, I risk a lurch or tire chirp. Like you, the truck is 'training me' to be a bit more patient, but my result is a super-smooth launch...no lurch. I wonder if the air suspension and/or additional weight softens my truck off the line...

 

[LaRamie]

Yes, ours does it too. It's just a combination of the overall set up I believe. You get used to it and where/how to play that spot in the brake pedal.

 

[DeanKing]

Thanks. Maybe it is just Delmonica trucks. The red makes em quicker off line Just weird it didn’t happen with higher gears on test truck but maybe it was just a short enough test drive.

 

[ExcursionDiesel]

My 3.92 5.7 Etorque moves immediately but I tip in on the throttle and it blends nicely. If I jump on the gas really quick, I get a strong launch, less civil. The motor is running and ready to pull with normal brake to gas transition. Are you a "both feet" driver by any chance? I can see where releasing the break and adding gas simultaneously would create an abrupt launch.

 

[DeanKing]

My 3.92 5.7 Etorque moves immediately but I tip in on the throttle and it blends nicely. If I jump on the gas really quick, I get a strong launch, less civil. The motor is running and ready to pull with normal brake to gas transition. Are you a "both feet" driver by any chance? I can see where releasing the break and adding gas simultaneously would create an abrupt launch.

No sir. I learned to drive on a stick shift. I do have quick reactions and sometimes I tend to go brake to gas really fast. Normal car that is no problem. I tried to back off that with the lurching but I am now seeing it jump just releasing the break with no gas. Not always. That’s why I am wondering if something is wrong.

 

[louz]

I have an eTorque / 3.92 truck, but I also have the ORG (ELocker), air suspension, and basically a heavier truck than yours. I've gotten used to the "golf cart launch", where I simply lift off the brake, wait for the engine to start and the truck to start rolling, and then ease into the gas. If I hit the gas pedal too quickly, I risk a lurch or tire chirp. Like you, the truck is 'training me' to be a bit more patient, but my result is a super-smooth launch...no lurch. I wonder if the air suspension and/or additional weight softens my truck off the line...

Mine does the same

 

[Edwards]

I test drove an eTorque truck with 3.21 gears and 20s. I am not sure if it was limited slip. It was very smooth. The eTorque system was not even noticeable.

I got my truck a few days ago. It has a 3.92 limited slip rear. Other than that, I can't think of what would be involved in the drive train that could affect this. About half the time, the truck lurches with a little burst of torque when I take my foot off the brake at a light. The engine restart is barely noticeable but the lurch forward is unsettling. If I am too quick to step on the gas, it is even worse so I have been training myself to give it a half second but it is still sometimes jumping on it's own before I can even hit the gas. If this was my Mustang, I would be pretty pleased with that. But this is a very smooth luxury truck and it seems kind of uncivilized to be lurching forward. Everything else about the truck is very refined except that.

I am thinking it is either the combo of the eTorque and low gearing or that something is wrong with my eTorque system. Before I go whining to the dealership and asking to test drive a lot of other trucks to compare, I wanted to see if anyone else noticed this.

Does anyone have this combination who could comment? Have you noticed this in yours?

I'm experiencing the same but I believe it is related to the transmission. I read somewhere that there is a hydro accumulator on eTorque models and that could explain both the stopping and starting lurches - I've got both. I think a transmission fw update could resolve this and I've wondered if Ram did most of their testing/tuning on eTorque with the 3.21?

 

[TimG]

I've noticed that on mine, it likes to lurch out the first time I put it in drive in the morning. Other than then, it's pretty tame on takeoff from engine stop to gas pedal.

 

[ExcursionDiesel]

I think what we are noticing is the Etorque electric motor spinning the motor up and producing torque to the driveline. Naturally the truck will move if the foot is off the brake and the motor is turning. The 3.92 axle produces more torque than the 3.21 at a given rpm so that's probably why it's more noticeable.

The trick is to not fully let off the brake early to get ready to go because it's going to move immediately. You can reduce pressure on the brake to start the motor. It won't stop again unless you move forward then stop. I actually like how it works. If I need instant hole shot response, I'll release pressure and let it start or press the A-off button. It's quick enough that I haven't needed it unless I'm just playing around.

 

[DeanKing]

From the responses it seems like this is “normal”. The thing that is weird is all the people and write ups talking about how there is no noticable affect on power. That’s are threads here saying that. There is clearly a difference. Sometimes.

 

[SpeedyV]

From the responses it seems like this is “normal”. The thing that is weird is all the people and write ups talking about how there is no noticable affect on power. That’s are threads here saying that. There is clearly a difference. Sometimes.

Even in my initial eTorque review back in July, I commented about the immediate nature of the start/stop system. The truck starts fast...fast enough to spin the tires while starting the engine.

 

[edrclark]

Mine does it as well. But I agree, the delmonico red makes it more noticeable

 

[jamesfg]

I have an eTorque / 3.92 truck, but I also have the ORG (ELocker), air suspension, and basically a heavier truck than yours. I've gotten used to the "golf cart launch", where I simply lift off the brake, wait for the engine to start and the truck to start rolling, and then ease into the gas. If I hit the gas pedal too quickly, I risk a lurch or tire chirp....... but my result is a super-smooth launch...no lurch.

Same here sans air suspension but I've got a 33" spare in the bed and about 200 pounds of on board air where the spare used to reside.

 

[th3duke]

I've noticed that on mine, it likes to lurch out the first time I put it in drive in the morning. Other than then, it's pretty tame on takeoff from engine stop to gas pedal.

what do you mean a lurche? I know a few of us have had some issues with the truck feeling like it's stuck in park or the e-brakes get stuck and then lunges.

 

[Gman]

I seem to recall an 'e roll assist' "feature" with the eTorque videos on the YouTube.

Yeah, found one here, mentioned at 2:09:

 

[Ortiz7983]

How do I know what gear ratio I have on my 5.7 Laramie?

 

[edrclark]

It should be listed on your build sheet or window sticker

 

[ExcursionDiesel]

If you're turning around 2000 rpm at 70mph, you have the 3.92 axle.

 

[Chris]

If you're turning around 2000 rpm at 70mph, you have the 3.92 axle.

*In 8th gear