6.4 -4th vs 5th gen comparo?

[RBinNC]

Do you use cruise control on the highway? You have to turn it on and then also hit set for the speed. You have to do this everytime you start your truck and head to the highway.

Disabling MDS or ECO is even easier just hit the minus. Everytime you drive the truck.

Funny, these forums are full of I need 1 more MPG. They give you a way to achieve that, an easy way to overcome it, and it does have an odd vibration at low speeds.

It is like the CAD. They did away with that stupid thing, but then brought it back to give 1 MPG claim.

Guess I am having a bad day, but my opinion is the MDS does what it claims and when I don't want it doing its thing I select a gear.

I drive most of the time with 4th selected...really wakes up the response of the truck, cause I get that same silly vibration in 5th or 6th going up the Mountain. The truck has the power to keep high gear, but it really just wants to be higher in the RPM range to growl like it likes. (Same thing with MDS at low speeds)

Good times

See but, cruise control is a convenience. If I want that, I engage it. Eco mode is forced on me, and makes my truck vibrate like I'm running over a rumble strip. So now I have to disengage it every time just to drive normal. There's a difference. Maybe mine is worse than average, I don't know. I took it to the dealer and they ordered new dampers for the active noice cancellation, so hopefully that fixes things? I don't know.

I will return the truck over this though if it's not remedied. Sorry I'm not paying to have a brand new truck vibrate my seat and steering wheel around town going in and out of Eco mode.

 

[redman4455]

I just bought a superchip flashpaq and turned it off on my 08 1500. Couldn't stand it either, but it's easy to disable and I wouldn't have thought about returning the truck over it.

 

[392DevilDog]

@RBinNC I hope your dealer can make it better, or maybe a nice member here can offer you use of their scanner and turn this annoyance off.

My friend felt the same way over it, and it only happen to him going through one school zone on the way home, refused to hit the gear shifter and refused to tap the gas. Guess different people have different priorities.

He did say his Powerwagon with the 4.10 didn't do it, but the 3.73 truck did.

He traded for a Chevy, he misses his RAM, would gladly hit the selector now.

 

[PCT]

I really tried to order an f250 with the 7.3, but Ford would hardly come off MSRP at all. Same went for the 6.2's. I had recently bought a '16 f150 5.0 4x4 single cab long bed which I really loved. Truck was fast as hell and quiet on the highway. Got 20 mpg and had a 20 gallon tank. Ultimately I wanted a crew cab but was not willing to give up the long bed, which pushed me into the 3/4 ton bracket. Ram had a nice salesman and they were ready to deal. I told Ford I was ready to buy that day and they kept playing games, wasting time. They only came off MSRP 2K as their best price. So out the door I went. Been driving Ford's for my entire driving life (almost 20 years). So this is my first ram. Enjoying it outside of the MDS thing. It vibrates like rumble strips and is droney on the highway.

Just set gear selector to 6-8( depending on trans) of you don't want it .

Sent from my SM-G973U using Tapatalk

 

[RBinNC]

So I took about a 200 Mile road trip in it today. Got more acquainted with the truck and enjoyed myself.

It's MOSTLY pretty seamless on the highway and worse around town, but if it's under load just right in Eco mode - a mainly flat area and right at 1900 rpm, I can have the radio on and not hear it but I feel it in my seat, steering wheel and especially the gas pedal.

I expected the dealership to tell me it's normal. Tech was very down to earth and said he'd look into a software flash, but when I got back they said the dampers were noisy in the active noise cancellation. So let's just hope there's a genuine defect there and it'll get solved.

Showed my family the truck today and everyone was quite impressed. Mind you I'm from a Ford family. I'll always be a Ford guy. But if I can get this vibration handled and the truck treats me right, it may be in the family a long long time.

 

[RBinNC]

Will know later next week when the dampers come in and are installed.

For what it's worth, this is a 4.10 rear. So that 1900 rpm is specific to that on my 8 speed

 

[RandomRam]

Will know later next week when the dampers come in and are installed.

For what it's worth, this is a 4.10 rear. So that 1900 rpm is specific to that on my 8 speed

My truck also has 4.10s. I bet the active noise system is the culprit on yours, especially since the tech went that way so fast.

I’m reminded how quiet this truck is every time I drive my wife’s Subaru. The Subaru is way louder cruising down the road than my 2500 even when MDS kicks in. Makes MDS that much more noticeable though.

 

[Trailmaker]

MDS is a non issue with higher Octane. Try it if you don’t believe me. I have 14k on my 19 and only use the recommended mid grade (91 for me) and this is never an issue. Truck is programmed to handle the 4 cylinders on a speed up timing. Also it is a difference of 4 mpgs when you leave it active.

 

[Scott L Napier]

MDS is a non issue with higher Octane. Try it if you don’t believe me. I have 14k on my 19 and only use the recommended mid grade (91 for me) and this is never an issue. Truck is programmed to handle the 4 cylinders on a speed up timing. Also it is a difference of 4 mpgs when you leave it active.

I have only 500 miles or so on mine..but really 4 MPG different ?

 

[Trailmaker]

I have only 500 miles or so on mine..but really 4 MPG different ?

Yes sir I played around with it for a few tanks of gas. 500 miles? You won’t see better mileage till the 2500 mark or so. Then change your oil but stay synthetic.

 

[ticat928]

MDS is a non issue with higher Octane. Try it if you don’t believe me. I have 14k on my 19 and only use the recommended mid grade (91 for me) and this is never an issue. Truck is programmed to handle the 4 cylinders on a speed up timing. Also it is a difference of 4 mpgs when you leave it active.

Lugging an engine at low rpm creates vibration, with today's computer controls one does not get pinging or detonation on low fuel quality, instead timing is pulled back and fuel enriched so much, that low speed torque output suffers greatly to the point 4 cylinders don't pull the load, vibration.

unfortunately 93 octane that gives much better low speed torque output (less vibration when only 4 cylinders are loaded) cost 0.60/gal more.

The gas mileage improvement on higher octane is not enough to offset increased cost.

I run regular in all my cars even though premium is specified, as long as i keep rpm's up via manual shifting no issues, i learned that from an automotive engineer, keep cylinder pressure down and regular will do the job

 

[tjfdesmo]

I have only 500 miles or so on mine..but really 4 MPG different ?

Never made a lick of difference on my '15.

 

[Trailmaker]

Never made a lick of difference on my '15.

If you had a 15 with a 6.4 you did not have the 8 speed. So you can not compare. I was talking with someone with a new truck that will see a difference with mds engaged.

 

[Trailmaker]

Lugging an engine at low rpm creates vibration, with today's computer controls one does not get pinging or detonation on low fuel quality, instead timing is pulled back and fuel enriched so much, that low speed torque output suffers greatly to the point 4 cylinders don't pull the load, vibration.

unfortunately 93 octane that gives much better low speed torque output (less vibration when only 4 cylinders are loaded) cost 0.60/gal more.

The gas mileage improvement on higher octane is not enough to offset increased cost.

I run regular in all my cars even though premium is specified, as long as i keep rpm's up via manual shifting no issues, i learned that from an automotive engineer, keep cylinder pressure down and regular will do the job

I won’t argue this point. Mopar made the truck to run Eco effective on mid grade. 93 is premium and as you see in the message you quoted of me I said 91. $0.20 difference at 4mpg better. Almost a wash with zero issues with the system alternating cylinders. Yes the computer can adjust to the low octane. But what do you get... Vibration. Run a full tank of mid grade before you reply, as I suggested before.

 

[RBinNC]

For the record, dealer replaced the active noise dampeners and it did not resolve the issue.

As for the octane suggestion that does not fix it either. Ran a tank of 93 when I first got it (salesman filled it with that with me there) and I still had the same issue. I've since been running mid grade which is 89 by me and issue is the same.

 

[Trailmaker]

For the record, dealer replaced the active noise dampeners and it did not resolve the issue.

As for the octane suggestion that does not fix it either. Ran a tank of 93 when I first got it (salesman filled it with that with me there) and I still had the same issue. I've since been running mid grade which is 89 by me and issue is the same.

Shift points are off?
Sorry friend...hate to hear you can’t enjoy your new truck. If you lived close, I would let you drive mine to insure that it is not all 6.4. My 5.7 did that and it was because it was misfiring on cylinder 3. But is has 106k on the OD.

 

[RBinNC]

I've begun to get used to it, and it only does it in that exact moment (1900 rpm). I'm hoping Chrysler engineers come up with a fix. I might try and see if I can drive another 6.4 at the dealer to see if it does the same thing.

 

[Mega-Hemi]

I notice my MDS as soon as it kicks on. Feels like driving down the rumble strips on the highway. I've only got 170 miles on her so far so I'm hoping it will smooth itself out as it breaks in. I've just been locking it out for now.

 

[RBinNC]

I notice my MDS as soon as it kicks on. Feels like driving down the rumble strips on the highway. I've only got 170 miles on her so far so I'm hoping it will smooth itself out as it breaks in. I've just been locking it out for now.

Yep. Just like mine. Glad I'm not the only one.