[Archived]

I would give Ken a call out. He can give you more info. Just got back from my gear guy so going to make big gear change myself . I don’t have the problems with modern egr controls you do: mine being a 2000 yr engine. Allison has a new 10spd automatic just out. I’m using a 10spd Eaton autoshift. 2.93 rear gear was able to fit in the case that is in the 98 XLE(was 4.56)- 315 80r 22.5 rubber. Bob

[Ed]

Car guy….if my records are correct the two most significant things you can do will be to drop your speed down 10 MPH and reduce the weight you are pulling as much as possible.

Aviators used to say they could go as fast as you wanted. Just let them know how much you wanted to spend. Same thing is true with our buses.

[Archived]

Most of the time running at 62-63 mph feels good. Just sit back, engage the cruise and relax. At this speed we won’t break any records getting from point A to point B. The trip is a pleasure and I’am not at all stressed. We enjoy the open road and get some chance to see the sights.

My other concern is wear and tear on my bus which has to be much less bounce and shake due to road condition. While on this subject, most favorite running time are summer nights. Those windshield bug hits…. keep you awake.

[Rodger]

Bounce and Shake, is that a Marathon thing? I don’t experience any of that in my Liberty, what say you boy’s?

[Archived]

I say poor Al doesn’t want to shake any of his air fittings loose after spending six months chasing leaks.

[Bob]

Holy crap….late at night and getting a quick post off. What have I done ?

One little slip of the key board and those Liberty guy’s can’t pass up.

Pete and Re-Pete both owning Liberty’s now ……we might have a problem here.

[Fred]

Settle down. Pete knows all our coaches have the same shake rattle and roll because of the Prevost chassis.

He was just pulling your Marathon chain a little and what did you do? You rose to the occasion!

Signed,

Re-Pete

[Archived]

If you really want to experience shake, rattle and roll, visit the Los Angeles area. Must be the worst roads in the US. Once you get to northern CA or into Nevada/Arizona, roads improve nicely.

[Kevin]

Even though we want to drive these huge vehicles, we still want them to get reasonable fuel mileage.

I was told on the new bus we’re having built that has the new Volvo engine, weighing 53,000 lbs. (wet), we should expect about 6.5-7 mpg. I like to drive on the slow side which is 55 mph in California and I’ll move up to about 60-62 mph if there is not ‘towing’ speed limit.

Our current tow vehicle weighs a little over 3,400 lbs. and I will continue to tow this vehicle with the new coach. It probably wont’ make a huge difference since it’s rather light.

Mark

[Bernie]

FWIW

We drove approximately 1500 miles . Computer said 6.6mpg ran the speed limit 65+- towing H2.

[needtocamp]

5 to 7 MPG with the new engines is about as good as it gets,2004 and forward you don’t have the luxury Ken has with bus the EPA makes sure of that

.I read where the EPA says emissions only added $1,200 to $1900 operatering cost for each truck in a year lol FWIW the Paccar MX 13 engine has the best fuel mileage of any class 8 truck engine according to the test they are 8 to10mpg with 80,000 lbs loads I had a chance to visit the plant in MS it is a neat place everyone should visit if given a chance to see the graphite iron engines being built

The Cummins ISX 13 is second ,DDC13 is the 3rd rated for MPG followed close by the Volvo D13 according to Diesel Magazine fwiw

[Jim]

FWIW, when we were at Prevost Nashville this past fall, there were 3 Senators entertainers (Volvos) all with the top end of the engines off. Don’t know the mileage. Just saying.

[needtocamp]

I find an 8 to 10 MPG performance in an 80,000 lb. truck to be bordering on wishful thinking.

That is especially true in my mind if the engine is an EGR engine, the truck is driven up and down hills, if the truck encounters head winds, and the measurement of mileage was in the real world.

I’m not suggesting our coaches are pacesetters when it comes to delivering fuel economy, but I have data on about 400,000 miles of driving my three coaches, and can say with certainty over thousands of miles and hundreds of refills unless the new engines have some as yet secret technology I seriously doubt the average in service mileage at 80,000 lbs exceeds 6 or 6.5 MPG

While the engine manufacturers would like us all to believe their goal is to produce an engine whose MPG exceeds all others, the reality is every single one of them has to design an engine whose prime objective is to meet the EPA standards. Every other feature from longevity to fuel mileage is secondary to that requirement because if they don’t meet the EPA standards they cannot sell the engine no matter how good it is.

[John]

You are wrong about not being able to sell a engine that does not meet EPA requirements Naviastar( IH) has been doing it for years they just pay the $19000 fine for each engine and keep making the engine they are just now testing the 2010 regulations Volvo and Cummins have been having fits about it

I read the test on the PeterBuilt MX 13 in Diesel Magazine a few months back it may be garbage but WalMart is big on the idea fwiw

[Steven]

Sorry, but that is not true about International Truck. They are using Cummins EPA approved aftertreatment and dropped plans for their own 15L engine and are using the ISX instead.

They attempted to go their own route and not use the DEF, but could not get to the final nox levels they needed to be at. That was what the other engine mfgrs were whining about, that International had a competetive advangtage over them because they did NOT use DEF (at that time). If they could have gotten it to work, it would have been a HUGE advantage!!

I just had dinner with my old Service Engineer for International and he said that the Cummins aftertreatment and the ISX were working very well.