MDS delete or not?

[bluecheese]

Ok, it’s official that a cam & lifters are going to be replaced. Shop wants to know if I’d like to delete the MDS in order to lower the risk of potential lifter failure in future. Different components + tune will be needed. Shop says it will affect my fuel economy.

My question is this…. How much fuel does the MDS system actually save? Will I notice a major decline in fuel economy? I currently get approx 650kms per tank of gas on 60/40 split of city/hwy driving. I also drive like a little old lady so I’m light on the gas. Any experiences or comments??

My only experience with your question is turning off the MDS using the gear buttons every time I drive the truck for the past 3 months. Before, I was averaging 16.5 to 17.5 mpg. Since turning the MDS off, I've been averaging 17.5 to close to 19 mpg.

 

[Dusty]

Most respondents here will lean toward deleting. Bear in mind the population here are enthusiasts and 99.99% of trucks out there the drivers never heard of MDS, don’t care.

I’m not particularly a fan myself, but I don’t hate it, and I can see the mpg bump up significantly when it’s running on 4.

AFAIK there’s no evidence that MDS operating causes lifter failure. Which is not to say Hemis don’t have issues with premature lifter failure- they certainly do.

Somewhere in here is a survey of which lifter failed and many were not the MDS cylinders.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, factory dual exhaust, 18” wheels. Build Date: 3 June 2018. Now at 87183 miles.

 

[frankherche]

My 2010 5.7 has 206,000 Mi on it. It ran with MDS engaged 90% of the time on my 10 mi commute to work for 5 years. Engine has not been touched except for regular maint.

 

[73-Cudah2]

I deleted them with my new engine 3 weeks ago. I plan to keep my truck 10 or more years.
it has 149,000 on it now.

 

[BuschLatte420]

I only notice my MDS engage sometimes a little bit, it’s like it just kicks on or off, driving 70 MPH on thruway with 3.92 gears and KO2’s I don’t even think it drops to 4 cylinders. Thing just drinks if it wants to drink. Now going 35 mph through town it might get better. Anything over 55-60 mpg is out the tailpipe!

 

[LIFTED-]

I am doing the MDS delete.

I noticed that there are little magnets with (4) prongs on them under the solenoids.

My inclination is to get rid of them...

Has anyone done this?

 

[Spree]

I have read this thread about 3 months ago and thought I would turn it off every time I got in it, just to see what happens. 26 miles one way to work at 50+ MPH. I get around 2 MPG more with it off and it runs better.

 

[BuschLatte420]

I have read this thread about 3 months ago and thought I would turn it off every time I got in it, just to see what happens. 26 miles one way to work at 50+ MPH. I get around 2 MPG more with it off and it runs better.

Funny how technology works LOL