[DON]

We installed the Ugly Fix 11 months ago. Our average mileage increase is appropriately 0.4mpg. That’s about a 7% increase which ain’t bad.

The biggest improvement for me was the near total elimination of the turbo lag. Our coach was a dog off the line until about 1500RPM where it really came alive. This usually occurred at the appex of a left hand turn in traffic sending things flying in the coach causing my wife to question my sanity and driving ability.

[needtocamp]

If the EGR is defeated either by programming or the use of the Ugly Fix the tube from the EGR heat exchanger to the intake manifold needs to be plugged or somehow blocked.

I did not find a significant improvement in mileage immediately. Initially it started with a .2 to .3 increase in MPG, but over time I have seen the mileage increase from what I think is the engine cleaning itself up internally with the sooting that comes as a result of EGR being cleaned out.

But if anyone is interested in improving mileage you don’t need to modify your engine. Just slow down. Your coach is a recreational vehicle and the faster you drive the less time behind the wheel you have to enjoy it.

[Archived]

So is there a consensus of opinion as to what the most ecomonical speed (assuming it’s not something a bit too slow for general hwy traversing!) is? 50? 55? 60?

I’d be more than happy to drive at 55, but once you start getting down to 50 or so, (unless it’s a slow road anyway) then enjoying the scenery lasts a bit too long. 🙂

I’ve read in a few places that matching your speed to the peak torque speed is the most economical. Have to say, I’ve tried this in my truck and I can’t say as I could tell any difference over just keeping it under 60.

Thoughts anyone?

[Steve]

I don’t drive for mileage so I cannot say the best for economy, but I know my 61 to 62 that I run consistently for ease of driving is giving me better mileage than 70 or even 65 MPH.

I drive so I am nearly the slowest on the road, but not so slow to be a hazard. A number of trucking companies are governed to 62 MPH so I am not alone. My speed allows me to rarely require a lane change or change in speed to compensate for slower traffic and the lack of opportunity to get into the passing lane when needed. At my speed most drivers pass me so I can relax while driving and let the cruise control manage the speed.

I would guess best economy is lower speeds, but at some speed I am sure the transmission is near the point where it will hunt as the road encounters slight up and down grades.

[Dewey and Tina]

Andy, I drive 65 and still wonder at times if that’s too slow, but I’m comfortable. Best mileage is never going to be consistent between vehicles so pick where you are comfortable with balancing your desire to get there and economy.

I’m going to review the ugly fix web site, but I don’t believe they say the blocked tube is necessary. Let me just say, I’m happy with the immediate mileage increase.

[Archived]

I doubt if you will experience a mileage increase of greater than .2 to .3 unless you block the tube.

The manufacturer’s claims of mileage increase on the Ugly Fix site is wishful thinking.

If you have not kept extensive records of your fuel useage you really do not know what your baseline fuel consumption is, and if you are not consistent in your cruise speeds, idle time, etc mileage tends to be all over the place making evaluation even more difficult.

But installing it will make you feel better.

[Bradley]

The numbers are what the numbers are, Jon. 5.6-6.3.

I am pretty consistent. If you were to ask if my drive home was 10k miles the answer is obviously no, but I did just make that drive last month with the results shown above. The only time I have ever gotten better than 6 was without a toad, and have never gotten 6.3 before.

[Karl]

I will believe the numbers if you show me they are 10,000 mile averages. There is absolutely no way a few refills will provide sufficient data to use to represent your mileage. There are so many variables, some of which can have a significant impact that only a long term accumulation of data can provide valid results.

I have a record of the miles and gallons for 25 years of coach ownership, spanning an 8V92, a 12.7 L Series 60 and now a 14 L Series 60 and I know for sure calculated mileage from tank to tank can have a very wide spread.

The message center display of mileage may or may not be accurate, but even if reset after every refueling it does not compensate for trips using or not using OTR, hills, headwinds, the weight of the toad or not towing, driving speed, point at which the fuel nozzle clicks off, etc. Until the variables are averaged the data is invalid.

[Bradley]

Well, I must disagree. The data is NOT invalid, though you are free to refuse to accept it. There is nothing I can do to change your personal criteria, but mine do not include 10,000 miles in travel to see a trend. Perhaps that is my physician’s training…..waiting to make a decision can make someone dead.

I drive consistently. Same route as last month. Same coach. Same OTR. Same toad. Same speed. Same leaking CAC. Obviously I am not measuring winds. And while the message center may be off, it’s most likely off the same this month as last, and the same as last year, and the same as always.

Again, I have never seen over 6 with a toad (notice that I can tell there was a difference in driving standards here) prior to installation of the chip and a 0.3 mpg difference above that IS significant. I am looking forward to continued accumulation of more data including driving with no toad, but the preliminary as I reported in the original post is pretty darned good.

If I were to be argumentative I would point out that in those 25 years you have not likely filled at the same station let alone the same pump every time, nor have you checked the accuracy of the pumps at which you have filled, so it is likely that they are all inaccurate to some degree. At least my message center readout is consistent.

[Archived]

My message center seems very accurate and I rely on that for fuel numbers. I do keep a log to cross check.

[Archived]

While you may have controlled a lot of elements you have no control over winds which have a large impact on mileage or the inconsistency between pumps when refueling just to name two points. There are numerous factors including OAT which also comes into play.

Something as simple barely noticeable winds, 5 MPH on the nose on one leg and the other 5 MPG on the tail on another leg is the same as driving 60 MPH or 70 MPH which we know for certain is one of the larger impacts on mileage.

[Jackson]

Ah, the irony…rich dudes with million dollar busses trying to extract tenths of mpg. I can see eliminating EGR for other reasons, but not fuel milege alone. Geo.

[Bradley]

Good point George, as a non rich guy, I sure don’t worry over 3 – 4 tenths of a gallon, but the cost of oil at Jeff’s keeps me up at night.

[Larry & Diane]

I don’t know which group I fall into. I don’t care how much Jeff charges for oil in an oil change, but I’m concerned about what he might find under the coach when he is lifting it with his $60,000 worth of wheel lifts to change the oil. I did $500 worth of damage to the coach trying to get to a diesel pump to save 5 cents a gallon on fuel.

[David]

I want the best mileage I can get.

My previous coaches had long range fuel with the last one having 298 gallons. I did a happy dance as I drove past truck stop after truck stop. I enjoy truck stops about as much as I enjoy NYC subway restrooms. I only want to go into one when I really have to, and the less often the better.