Advice?

[DanAR]

Electronic range select,if you have an 8 speed,it's the Up/Down buttons on the right side of your steering wheel. Pushing the buttons till you see "8" on your evic,disables the MDS,but allows the transmission to still shift up and down through all the gears

Thanks

 

[Jesusplusnothing]

FWIW, on my 2019, sometimes I don't notice the MDS disengaging and sometimes I hear the "thud". I will say that I only leave MDS engaged on the highway as I find it annoying going in and out all the time the when I'm in town or on the country roads. On the highway MDS does add 1-3 mpg because it says engaged long enough to make a difference. Oh, and it has nothing to do with the transmission, when I hear the "thud" the transmission never changed gears, RPM never changed.

I'm pretty convinced it's the torque converter. What in your opinion do you think said thud/bump is?

 

[ramffml]

I'm pretty convinced it's the torque converter. What in your opinion do you think said thud/bump is?

It's not the torque converter. As been suggested multiple times, its the MDS going in/out. Just lock it out to 8th gear and enjoy life. You'll never feel that bump again. This is a very well known problem with the MDS system. You can worry about it or spend time at the dealer or just use the limiter and carry on.

 

[Tulecreeper]

Can you elaborate on this process a little more. What does ERS stand for in this case?

Electronic range select,if you have an 8 speed,it's the Up/Down buttons on the right side of your steering wheel. Pushing the buttons till you see "8" on your evic,disables the MDS,but allows the transmission to still shift up and down through all the gears

Yes, that. To engage it you have to hit the (-) button first, then hit the (+) button and run it up to "8". If you run it past 8 you have to start over again and hit the (-) button again. You can also use it to limit the gear it will shift up to, like setting it at 5 when coming downhill with a load so it won't shift higher than 5. Although I've only needed to do that a couple times as the truck is real good at taking care of that stuff by itself. If you have CC set, it will do a lot to keep it at that speed by shifting up and down to keep it within a couple MPH of the setting.

 

[Wild one]

Yes, that. To engage it you have to hit the (-) button first, then hit the (+) button and run it up to "8". If you run it past 8 you have to start over again and hit the (-) button again. You can also use it to limit the gear it will shift up to, like setting it at 5 when coming downhill with a load so it won't shift higher than 5. Although I've only needed to do that a couple times as the truck is real good at taking care of that stuff by itself. If you have CC set, it will do a lot to keep it at that speed by shifting up and down to keep it within a couple MPH of the setting.

On bigger hills i'll kick the cruise off,as it'll hit the brakes to maintain speed,then floors itself to maintain speed up the other side,lol

 

[Jesusplusnothing]

It's not the torque converter. As been suggested multiple times, its the MDS going in/out. Just lock it out to 8th gear and enjoy life. You'll never feel that bump again. This is a very well known problem with the MDS system. You can worry about it or spend time at the dealer or just use the limiter and carry on.

Sorry been told 2 things on here lol.

 

[Musky Mike]

I'm pretty convinced it's the torque converter. What in your opinion do you think said thud/bump is?

I don't think it the torque converter because I see no change in the RPMs and I don't really feel anything. I think it more of a sound, maybe the sound (firing) of the 4 cylinders starting back up, not sure. Sometimes I hear it and sometimes I don't.

 

[Jesusplusnothing]

I don't think it the torque converter because I see no change in the RPMs and I don't feel anything. I think it more of a sound, maybe the sound of the 4 cylinders starting back up, not sure. Sometimes I hear it and sometimes I don't.

Makes sense. My guess was torque had to drop. Idk what the torque is at 30 mph 1800ish rpm. I figured it had to be at least half what it is with 8 cylinders. So when you kick full power back on hitting the accelerator the tcm trys to compensate for the difference in power. I came to this conclusion based on what another guy on here said.

Honestly I'm super surprised that this information was so hard to find. Nothing at all about it in YouTube. As in no one talking about a bump.took me a few weeks to find out there was a thread on this site about it.

 

[ramffml]

Makes sense. My guess was torque had to drop. Idk what the torque is at 30 mph 1800ish rpm. I figured it had to be at least half what it is with 8 cylinders. So when you kick full power back on hitting the accelerator the tcm trys to compensate for the difference in power. I came to this conclusion based on what another guy on here said.

Honestly I'm super surprised that this information was so hard to find. Nothing at all about it in YouTube. As in no one talking about a bump.took me a few weeks to find out there was a thread on this site about it.

We've talked about it extensively on this forum and the 5th gen forum. It's like a little "fish bite" tug. Some trucks/conditions are much more noticable than others.

Torque at the wheels doesn't really drop all that much in 4 cylinder mode, like 90% to 95% of the fuel that was sent to 4 of the cylinders is now sent to the remaining 4 that are still firing. The engine is still putting down almost identical power numbers, except 4 cylinders are now really stressed running hard, and 4 are turned off.

 

[DanAR]

Yes, that. To engage it you have to hit the (-) button first, then hit the (+) button and run it up to "8". If you run it past 8 you have to start over again and hit the (-) button again. You can also use it to limit the gear it will shift up to, like setting it at 5 when coming downhill with a load so it won't shift higher than 5. Although I've only needed to do that a couple times as the truck is real good at taking care of that stuff by itself. If you have CC set, it will do a lot to keep it at that speed by shifting up and down to keep it within a couple MPH of the setting.

I tried it last night and it locked out my ECO light and from that the MDS shifts. Good to know - I’ll probably try to do that around town as going in and out of 4 cylinder mode at lower speeds seems pretty sketchy to me.

Thanks

 

[Jesusplusnothing]

We've talked about it extensively on this forum and the 5th gen forum. It's like a little "fish bite" tug. Some trucks/conditions are much more noticable than others.

Torque at the wheels doesn't really drop all that much in 4 cylinder mode, like 90% to 95% of the fuel that was sent to 4 of the cylinders is now sent to the remaining 4 that are still firing. The engine is still putting down almost identical power numbers, except 4 cylinders are now really stressed running hard, and 4 are turned off.

Interesting seems like a stupid idea to me. This other fella on here said 2019 + no tuner will turn it off. Diablo has one the pulsar that says it does turn it off and it doesn't mess with the pcm so you should be able to keep the warranty provided you just disconnect it before services. This seem right to you or is the other fella right?

 

[Wild one]

I tried it last night and it locked out my ECO light and from that the MDS shifts. Good to know - I’ll probably try to do that around town as going in and out of 4 cylinder mode at lower speeds seems pretty sketchy to me.

Thanks

All the Eco light means is you're driving in the most economical way,it can come on with-out the mds kicking in,but if you're in mds mode you're also usually driving fairly economical

 

[ramffml]

Interesting seems like a stupid idea to me. This other fella on here said 2019 + no tuner will turn it off. Diablo has one the pulsar that says it does turn it off and it doesn't mess with the pcm so you should be able to keep the warranty provided you just disconnect it before services. This seem right to you or is the other fella right?

You can just use the gear limiter or tow/haul mode to turn it off. As far as I know the Diablo "disables" it by tricking the system, basically just before it kicks in the tuner sends a little power bump which then requires more power than MDS can deliver so it stays off, it does this constantly so it's not really turning it off. I don't know if this has changed or other tuner can permanently disable it, I just use my gear limiter every time I put it in drive.

All the Eco light means is you're driving in the most economical way,it can come on with-out the mds kicking in,but if you're in mds mode you're also usually driving fairly economical

This was how the older trucks work for sure, but the newer ones (definitely 5th gen) ECO = MDS. I can go for months without seeing my ECO light on the dash, the second I forget to disable it the light comes on and I get the tug. Or, if I'm driving 60km/h on a rural road with gear limiter on, truck is holding steady - I can go for a minute like that, no light. Then keep speed steady and turn off gear limiter and 3 seconds later, boom, little tug and dash lights up.

 

[DanAR]

All the Eco light means is you're driving in the most economical way,it can come on with-out the mds kicking in,but if you're in mds mode you're also usually driving fairly economical

Well, I asked this question above and understood the responses to say the ECON light represented the MDS kicking in and out. Now, there are responses in contradiction. My limited testing with disabling the MDS indicates I can be rolling down a hill on closed throttle and the ECON light is not going to come on ever. That would seem to make MDS the go/no go parameter for the ECON light activation. Do we have a tie breaker vote?

 

[Tulecreeper]

Well, I asked this question above and understood the responses to say the ECON light represented the MDS kicking in and out. Now, there are responses in contradiction. My limited testing with disabling the MDS indicates I can be rolling down a hill on closed throttle and the ECON light is not going to come on ever. That would seem to make MDS the go/no go parameter for the ECON light activation. Do we have a tie breaker vote?

I don't actually know. I do know that I can go into my settings and disable my ECO light coming on even if my MDS engages.

 

[Jesusplusnothing]

Well, I asked this question above and understood the responses to say the ECON light represented the MDS kicking in and out. Now, there are responses in contradiction. My limited testing with disabling the MDS indicates I can be rolling down a hill on closed throttle and the ECON light is not going to come on ever. That would seem to make MDS the go/no go parameter for the ECON light activation. Do we have a tie breaker vote?

I'll tell you this I've put 250 miles on my truck using the gear thing on the steering wheel. No eco light and I cannot hear the mds kick on, and I have not once felt the bump/thud. So it is definitely turning something off. My vote is it's turning the mds off.

My vote is also that the ECO light comes on prior to mds coming on. As I cannot alway hear the change in exhaust when the ECO light comes on. Unless it's on for a second or 2.

For sure though the gear selector thing rids me of the thud/bump.

 

[Wild one]

Well, I asked this question above and understood the responses to say the ECON light represented the MDS kicking in and out. Now, there are responses in contradiction. My limited testing with disabling the MDS indicates I can be rolling down a hill on closed throttle and the ECON light is not going to come on ever. That would seem to make MDS the go/no go parameter for the ECON light activation. Do we have a tie breaker vote?

They must of changed it for the 5th Gens,as the 4th Gens didn't operate that way,they could have the eco light come on with-out the mds kicking in.My 4th gen doesn't have mds or the solenoids,hell it doesn't even have the solenoids wiring harness anymore,and it'll still turn the eco light on,lol
So it has to be a 5th Gen change

 

[DanAR]

Although I never really felt anything before that I associated with MDS operation, since I’ve tried the 8+ lockout, I have noticed the truck seems to run a little smoother in city traffic up to around 45-50 mph. My truck only has about 1400 miles on it.

 

[Jesusplusnothing]

To be f

Although I never really felt anything before that I associated with MDS operation, since I’ve tried the 8+ lockout, I have noticed the truck seems to run a little smoother in city traffic up to around 45-50 mph. My truck only has about 1400 miles on it.

To be fair my wife never felt it. Several coworks never felt it. I just over think things.

 

[Wmjohn]

I had exactly what you describe in my 2016. Ram had just provided a new tranny under warranty, and occasionally upon downshift, it banged so hard at times, I expected to see the rear end dropped in the road behind me.

The dealer installed updated tranny software and the problem dissappeared.