Hey guys. Here's my observation on the effectiveness of MDS.
A few months ago when I was making my 800~ mile trip to Canada my truck averaged ~17-18 mpg on the interstate at 70-75 mph through NC, VA, WV, OH and MI. This was before I got the tuner, t-stat, and e-fan, and MDS was still on. My most recent trip (last week) on the same route my truck averaged 14.5-15 mpg. Same speed. This was with the 180 t-stat, tuner, and e-fan and all other mods in my sig. MDS was turned off, throttle sensitivity was raised 10% (which I can understand a little loss in mpg as throttle is touchier). I understand the t-stat hurting it a bit but the e-fan should have compensated for that. On my drive back down to NC I'm going to leave MDS on and note my mileage then with all my current mods. What do you guys think?

Oh and these numbers are hand calculated. Not by the overhead computer.

 

hey man hope everything is going good up there. What about the weather??is it hotter out this time? Humidity? check tire pressure? were your new tires the same size as stock?

 

Humidity is about the same. Temp is a little cooler than in May by maybe 5 degrees but not a huge diff. 35 psi in all tires. Same size tires as before. I really think MDS did benefit me on the highway. Other than that the truck does feel smoother with the throttle sensitivity set back to 0%.

 

I dont mean to hijack but how do you like the predator? Performance-wise ofcourse.

 

rick myself and roberts both have the predator. I have a 93 CMR tune and love it. The big deal is the shift points for most, but with mine being lifted i was able to reset the speedo for my 35's and also because of my LT, and some other things i have i had a custom tune done and am very happy with it. The night and day difference is felt after the shift points are changed.

 

Roberts i have to say that makes no fricken sense as my truck after the e-fan now gets just over 15mpg with MDS off. You have smaller tires and lighter rims, no lift, and also yours is 2wd less wieght. I'm at a loss maybe check the spark plugs see if it is running rich or lean.

 

Alright I turned MDS back on and drove back to NC with it on. I averaged between 16.5 and 18 on the highway travelling between 65 and 75. This might not make a difference because I noticed that travelling at 75 mph the truck stayed in 8 cyl mode with the exception of travelling downhill. So on my way back home to NC I averaged 70 mph the entire time as opposed to 75.... Still, a 5 mph difference shouldn't make a 3 mpg difference but it would go into 4 cyl at 70 but rarely at 75. Overall, still, I would say that MDS does make at least a ~10-15% difference and is still effective. The biggest increase I noticed was cruising at ~35 mph in 4 cyl as opposed to 8 cyl. You don't need 8 cylinders to drive 35 mph so I noticed a pretty big gain there. I'd say MDS works the best from 35-68 or 70 mph depending on the road conditions.


Oh btw, Don, sorry I had to cancel dinner plans, I was feeling pretty jacked up today. Also, when are you guys PCSing to Cali?

 

should be getting check in dates this next week.