Everyone says that this MMO and PS adds 1-2+ mpg.....Well, I added a Volant intake, eliminated my Turbo silencer ring changed the oil at 3500miles with Rotella and added 16oz of PS and 8oz of MMO and I noticed a (-) 2 (minus two) mpg. What the HE!!?????
I was getting 20.4 mpg on long highway trips.......Now 18.6 ....city before16.2 now lucky to hit 14....granted the city driving I am a little more aggresive so I can hear that turbo/intake wissle.
I was always affraid to use additives in the pass thinking they could cause harm rather then good. This seems to be the case!
Any ideas?

 

I too have an '06 CTD and I used the "mix" from the start.

Just like you I got 20+ so I cant say if it helped me from the start but the extra lube (always good ) has got to be worth something.

Then I made some (alot all at once) changes (as outlined in "intake help" ) and wasnt happy.

Who knows what the issue really was but I can say that regardless of the intake issue I had (or didnt have [&:]) I have become a firm beliver in the Quadzilla XZT (non adjustable) module. It gives an extra 65 HP plus 165 fpt. It also boasts an additional 1-4MPG.

I paired it with the BD tripple dog and have plenty of extra power with the BD at tow/perf (combined with the ZXT) and still get 20 at 70-72mph.

Just my exp so far.

 

I found that using my AFE stage 2 intake kit with the massive filter dropped my mpg by 1.0~1.5 mpg. this is due to the turbo being able to pull more air and spool up faster. with my stock 4" exhaust I was getting between 16~16.5 mpg avg, opened up the exhaust and that dropped down to 14.5~15.0 mpg, the turbo spooled like there was no tomorrow. real quick and high boost... with the afe intake on. so for the hell of it I went back to the stock intake and my mpg went back up 1.0 mpg, low end torque seemed to come back as well. however the turbo almost never reaches the boost levels it did with the afe on.

long story short... open up the intake and/or exhaust and it's going to affect your milage, spoolup times & peak boost. I think there is a sweet spot in there some where between the intake & exhaust that would make it perform well. If I ever get the motiviation & free time, I'll dive into it and let you all know what I find.

 

I see what you are saying and it does make sense. However, when I was into the import car seen the intakes made a difference in MPG and I was running a supercharger. Furthermore, the companies claim better, mpg overall. And about your theory of spool up rate etc. that could be true as far as starting and stopping, but at a cruise going about 70 you would think (i would) if the intake is able to breath better it would cause less drag (what ever word you would like to use) and create less effort for the engine to breath; resulting in better mpg. But I am no motor head!
Thanks for the reply guys!

 

At cruising speed your motor will have a certain amount of hp/torque at any given rpm based on throttle position. change the intake or exhaust and the hp/torque at that rpm will change. if it goes up, your throttle position will be lighter than before to maintain the same speed, if it goes down, then your throttle position will go up to maintain your speed.

think about it, if you have say 300 ft lbs of torque moving 7000 lbs of truck at 70 mph/2000 rpms then open up the intake & exhaust so your flowing more, your low end torque may drop @ 70 mph/2000 rpms if you open it up too much.

I experimented with my 2000 gasser and now my 2005 ctd... it's the same for both types of motors. open it up front & back and the top end is really happy, turbo spools much faster which causes your pcm to feed it more fuel.

I have kept track of my diesel usage for the last 2 months and have changed different things and watched the milage change with it. the butt dyno concurs with every change.

 

Steve...makes "cents"..I forgot, I guess, that I am driving a big bertha now!