Ram 6 vs 8 speed

[stevemorris]

all else being equal, engine, rear end ratio, what's the difference between the 6 speed and 8 speed offered by Ram as far as towing is concerned

[mich800]

VernDiesel wrote:
Page 1 of this thread Wilbur1 asked why don't they offer the eight speed with the 6.4 2500.

Useing the the Ram reps comments in the link above was to answer the question posed & being bantered in this thread. At least that was my understanding. I didn't copy paste and read the link. I suppose the question there was more general as in with Duallys and using the Cummins.

I may have misinterpreted your comment. I thought you meant the rep was incorrect about the statement " Ram reps comments is that the 2500 gas HD isn't rated to tow 30k or carry 7K" where they never mentioned 2500 only the HD lineup.

[VernDiesel]

Page 1 of this thread Wilbur1 asked why don't they offer the eight speed with the 6.4 2500.

Useing the the Ram reps comments in the link above was to answer the question posed & being bantered in this thread. At least that was my understanding. I didn't copy paste and read the link. I suppose the question there was more general as in with Duallys and using the Cummins.

[mich800]

VernDiesel wrote:
The stupid part of the Ram reps comments is that the 2500 gas HD isn't rated to tow 30k or carry 7K either. At least he got the part right about the eight speed not being able to hold greater weights in Park on a hill without the risk of it breaking & rolling down the hill.

The question wasn't why not in the 2500 but in the HD lineup.

[VernDiesel]

The stupid part of the Ram reps comments is that the 2500 gas HD isn't rated to tow 30k or carry 7K either. At least he got the part right about the eight speed not being able to hold greater weights in Park on a hill without the risk of it breaking & rolling down the hill.

[smurfs_of_war]

Found a blurb about it online. Ram reps reaponses:

http://www.tfltruck.com/2015/05/ask-tfltruck-ram-trucks-questions-answered/

"WHAT ABOUT THE 8-SPEED AUTOMATIC IN THE RAM HD TRUCKS?

The short answer is: no. The existing 8-speed TorqueFlight automatic transmission is not rated for heavy duty requirements of towing up to 30,000 lbs or hauling over 7,000 lbs. It is also not rated to hold this much weight on an incline in Park."

[VernDiesel]

Beh.. slow down & comprehend what been written. No problem with handling the power of the 5.7 or 6.4 in the HDs. It's being able to safely hold 10,000 pounds when it's parked on a hill.

In my case with conservative tune my 1500 Ecodiesel makes about 485 TQ ie more than the 429 TQ of the 6.4 but the 1500 only has a GVWR of 6950 not 10k like the 2500.

[ib516]

FishOnOne wrote:
The ZF 8 speed is going to be much more reliable than the 6 speed and if much more efficient.

If they can make it able to handle the power, the 8 speed and the 6.4L Hemi would be an awesome combo.

[smurfs_of_war]

Grit dog wrote:

smurfs_of_war wrote:
8 speed was the nicest towing transmission I have ever had in a half ton. Always knew what gear it needed and when you dropped gears going down a grade it stuck like a magnet with basically no input of the brake pedal. I had 3.92s in it.

As for it's absence in the HD line up- it has been covered in depth on a few forums. It has to do with the ability of the transmission not being rated to hold the full GVWR of the truck when parked- so i assume the pawl or something was the weak point?

Which is so weird because that same basic 8 speed with heavier internals is backing 700hp cars. I have to believe it would stand up behind the 6.4 Hemi no problem.

I think it will handle the output just fine (if memory serves it was rated to 570 ft lbs) but the coles notes version of the discussions was that it was not rated to hold the full GVWR of the vehicle (so 10k or more) when parked. Meaning there is a weak link somewhere, I just don't think it's to do with the delivery of power.

[Grit_dog]

smurfs_of_war wrote:
8 speed was the nicest towing transmission I have ever had in a half ton. Always knew what gear it needed and when you dropped gears going down a grade it stuck like a magnet with basically no input of the brake pedal. I had 3.92s in it.

As for it's absence in the HD line up- it has been covered in depth on a few forums. It has to do with the ability of the transmission not being rated to hold the full GVWR of the truck when parked- so i assume the pawl or something was the weak point?

Which is so weird because that same basic 8 speed with heavier internals is backing 700hp cars. I have to believe it would stand up behind the 6.4 Hemi no problem.

[FishOnOne]

The ZF 8 speed is going to be much more reliable than the 6 speed and if much more efficient.

[mtofell1]

Forget the 8spd in the HD line - I'd settle for a 6spd in the Hemi that wasn't designed by a moron 🙂

The gear ratios are borrowed from the diesel counterpart and really aren't ideal for gas. I think Ram tries to keep costs down by borrowing parts back and forth between models. I suppose every manufacturer does this.

[smurfs_of_war]

8 speed was the nicest towing transmission I have ever had in a half ton. Always knew what gear it needed and when you dropped gears going down a grade it stuck like a magnet with basically no input of the brake pedal. I had 3.92s in it.

As for it's absence in the HD line up- it has been covered in depth on a few forums. It has to do with the ability of the transmission not being rated to hold the full GVWR of the truck when parked- so i assume the pawl or something was the weak point?

[Santa_Fe]

8 speed all day...sooooooooooo silky smooth.

[boshog]

The 8 speed offers a larger range of returned value. Coupled with a 3:21 axle ratio, the 8 speed offers lower off the line power than the 6 speed with 3:92s. In the higher gears, you will get improve economy with lower RPMs at highway speeds.

You have the option of manually selecting a gear to optimise the towing power needed.

I tow a 7,500-pound trailer/tractor combo around town with my 2013 8 speed with 3:21 axles, never felt the need for more power. The 8 speed does a nice job of keeping the engine it is power band.