Torque wars continue in the diesels

ShinerBock wrote:
I will also note that the reason for torque management is not just for the drive line. It is also mainly to keep from popping head gaskets due to high cylinder pressure. Combine the quick boost from a VGT, increased timing, and more fuel at lower rpms and you have a recipe for a popped head gaskets. Big power at low rpm is also very hard on the rods. Ever notice how head gasket failure was a common issue with the first few years that GM(LLY), Ford(6.0L), and, Cummins(6.7L) added VGT's and how torque management became a complaint shortly there after? Non-VGT diesels do not have to deal with this as much.

This is also probably one reason why 2015-16 VGT 6.7L Powerstokes felt a little slower of the line than the 2011-14 non-VGT Powerstrokes since Ford did not have to utilize torque management as much in non-VGT engines.

Having had a 2001.5 with a loose stock TC and a 89 % DTT, and then a mis-match loose TC on second rebuild, which was swapped out for a tighter one, I have to say my 2015 Aisin is not loose. I would say it is about right for towing and bobtail use.

Chris

I’m making numbers that would eat this truck alive towing the same weight (I’d be over on the pin lol but I’d win lol anyway) also on a stock trans at its limits and the rest all has 377k and ticking but the TC issue is somthin that can’t be messed with with efi? Mine locks up but it seems to be if I switch to a higher tune from the next that it’ll stay locked but yeah you will notice it switch from what I have tunes 1-5 . It makes a big difference now can only imagine how it’ll be with new lift pump ??it’s nice to be able to pull pass semis that can’t be built as well while towing a large load

Sweet!
I got a legit shot at getting a factory 450hp/1000tq truck in the near future......

To he!! With higher HP. Lower the dog gone price.

4x4ord wrote:
I am not certain but I think you guys haven't got a clue what you're talking about as far as how torque management works. When I put my truck in 4 low with a 30,000 lb trailer hooked up and sunk in the mud the amount of torque going to the rear wheels is huge. .. The driveline has to be able to handle full engine torque in 2nd gear while the tranfer case is in high range. My limited understanding of torque management is that the computer backs off fuel delivery during shifts in order to limit high torque on the clutches before they have a chance to fully engage.

That is due to gear torque multiplication in the transfer case which is after the transmission. The amount of torque going in and being multiplied out of the transmission is still the same whether you are in 2 high or 4 low. In the case of your truck, 4 low multiplies the torque coming out of your transmission by 2.72 and then additional amount depending on your front/rear gear ratio.

I am not certain but I think you guys haven't got a clue what you're talking about as far as how torque management works. When I put my truck in 4 low with a 30,000 lb trailer hooked up and sunk in the mud the amount of torque going to the rear wheels is huge. .. The driveline has to be able to handle full engine torque in 2nd gear while the tranfer case is in high range. My limited understanding of torque management is that the computer backs off fuel delivery during shifts in order to limit high torque on the clutches before they have a chance to fully engage.

I just picked up my brandy new 2017 F350 Lariet Diesel Dually this last week. I can't wait to tow with it. Upgraded from a 2012 F250 gasser.....

ScottG wrote:

ShinerBock wrote:

LanceRKeys wrote:


For those of you that are getting those numbers (ShinerBock), where is it most noticeable? If you were to turn your tune off while pulling your RV, where would you notice it first?

I cannot turn my tune off while driving, but I can switch between power levels on the fly. It is tuned via EFILive with a CSP4 switch. It is a 4 position switch the goes from 390 rwhp/802 rwtq in position 1, 450 rwhp/948 rwtq in position 2, 470 rwhp/1020 rwtq in position 3, and 515 rwhp/1105 rwtq in position 4. If I go wide open throttle in position one and switch to two or three while still at wide open throttle, then you will feel a surge in power as you switch to each position.

I generally stay in position two empty or when towing light and in one when I am towing heavy. I don't really want to go higher than that on the stock trans and torque converter.

The torque converter on the 68RFE and Aisin is too inefficient compared to Ford and GM's at putting the power to the ground unlocked in my opinion and needs a lower stall speed. This is one reason why it takes off so slow because it just spins wasting engine power and doesn't really take off until locked. A triple disc TC with a lower stall speed is a night and day difference from stock even without adding power.

It's not the torque converters, it's the puter limiting torque in lower gears to save parts. All manufacturers do this.

I know which is why I stated what I did in the following post. I was just commenting on what Lance asked me and added another reason why these two combos are slower in my opinion. There is a night and day difference in running the same tune on the stock converter on both these trans and an aftermarket triple disc converter with a lower stall speed. The pull from a triple disc with the lower stall speed unlocked almost feels like the stock one does locked while accelerating.

ShinerBock wrote:

LanceRKeys wrote:


For those of you that are getting those numbers (ShinerBock), where is it most noticeable? If you were to turn your tune off while pulling your RV, where would you notice it first?

I cannot turn my tune off while driving, but I can switch between power levels on the fly. It is tuned via EFILive with a CSP4 switch. It is a 4 position switch the goes from 390 rwhp/802 rwtq in position 1, 450 rwhp/948 rwtq in position 2, 470 rwhp/1020 rwtq in position 3, and 515 rwhp/1105 rwtq in position 4. If I go wide open throttle in position one and switch to two or three while still at wide open throttle, then you will feel a surge in power as you switch to each position.

I generally stay in position two empty or when towing light and in one when I am towing heavy. I don't really want to go higher than that on the stock trans and torque converter.

The torque converter on the 68RFE and Aisin is too inefficient compared to Ford and GM's at putting the power to the ground unlocked in my opinion and needs a lower stall speed. This is one reason why it takes off so slow because it just spins wasting engine power and doesn't really take off until locked. A triple disc TC with a lower stall speed is a night and day difference from stock even without adding power.

It's not the torque converters, it's the puter limiting torque in lower gears to save parts. All manufacturers do this.

I will also note that the reason for torque management is not just for the drive line. It is also mainly to keep from popping head gaskets due to high cylinder pressure. Combine the quick boost from a VGT, increased timing, and more fuel at lower rpms and you have a recipe for a popped head gaskets. Big power at low rpm is also very hard on the rods. Ever notice how head gasket failure was a common issue with the first few years that GM(LLY), Ford(6.0L), and, Cummins(6.7L) added VGT's and how torque management became a complaint shortly there after? Non-VGT diesels do not have to deal with this as much.

This is also probably one reason why 2015-16 VGT 6.7L Powerstokes felt a little slower of the line than the 2011-14 non-VGT Powerstrokes since Ford did not have to utilize torque management as much in non-VGT engines.