Class 8 Truck modifications

[Goldenstate]

Long ago I was involved with servicing of diesel trucks and was astounded at the lack of fuel mileage. Fuel was cheap and management did not seem to care as it was part of the cost of doing business. Today with fuel costs once again on the rise, increasing big rig fuel efficiency has got to offer some serious rewards if executed well across a large fleet.

One thing not mentioned was the application of smaller high efficiency alternators. Another item was the ceramic coating of wheel bearings. Another item of interest might be the special coatings applied to the transmission and differential gears to make them far more slippery. That combined with the synthetic lubricants might make for some nice improvements.

Best of luck with your fuel savings program and keep us informed as to what you do and how well it works.

[freebeard]

I for one don't understand people who insist on driving something completely stock. Like they are the specific demographic the whole thing was tuned to. Here's a few more things to think about. First this:



A long box van is a special case aerodynamically. The length allows turbulent air to reattach to the skin. This is called fineness ratio. Find a member called aerohead and look at his posts or albums. There is a lot on cab-van spacing, buses drafting each other, etc. Also there is a member named Sheperd777 that is building the AirFlow Truck Company StarShip

The other thing is some work by Robt. Englar that came out Georgia Tech:

https://www.osti.gov/scitech/servlets/purl/770965

SAE TECHNICAL
PAPER SERIES
2000-01-2208
Development of Pneumatic Aerodynamic Devices to Improve the Performance, Economics, and Safety of Heavy Vehicles
Robert J. Englar
Georgia Tech Research Institute

https://books.google.com/books?id=yN...umatic&f=false

The Aerodynamics of Heavy Vehicles: Trucks, Buses, and Trains
edited by Rose McCallen, Fred Browand, James Ross

ebook from $124.54

https://www.gtri.gatech.edu/casestud...uel-efficiency

Case Study
Low-Drag Trucks: Aerodynamic Improvements & Flow Control System Boost Fuel Efficiency in Heavy Trucks

I'm not selling anything, I just want you to be happy.

[gumby79]

https://cumminsengines.com/uploads/d...whitepaper.pdf
This info from Cummins backs up many of your theories.

[craysus]

Originally Posted by teoman

How large is your fleet?

~150 trucks, plus a number of other vehicles.

[craysus]

Originally Posted by gumby79

This info from Cummins backs up many of your theories.

Read this one a few times Some nice easy to understand information in there!

[Hersbird]

Originally Posted by craysus

If an engine manufacturer could deliver the most efficient engine taking into account a lot of external sources, and other pieces, forums such as this would NOT exist..

Every single engine ever made by a manufacturer can be improved upon with aftermarket parts and tuning available.

Pulling a Cummins apart, and rebuilding it to improve V.E. (Basic porting / balancing) will increase its fuel economy greatly, extra parts such as lighter pistons with shorter skirts, removal of parasitic external forces on the engine, transmission improvements, exhaust and inlet improvements all GREATLY enhance fuel economy and can at the same time REDUCE emissions...however, they are costly to perform in the factory, and even more costly in the aftermarket..
Bulk manufacturers are run by bean counters...NOT by the engineers and designers...
I guarantee Cummins could build a 20% more efficient engine without trying too hard...just the cost increases of 40-50% per engine would make that engine unjustifiable..And training the half educated mechanical geniuses in most facilities to service a much higher tech engine with tighter tolerances would be nigh on impossible.
.

I say no way. They would take a 20% improvement if it doubled or tripled the price of the motor. Fleets just like you would scarf them up by the thousands over their competitors at International or Volvo or whoever. I also say any increase in economy is going to put NOx emissions over what the government will allow. I personally don't think that's a problem, but that is what is holding the manufacturers back. If you are willing to throw NOx to the wind then you can accomplish whatever HHO (which just never is going to make scientific sense) would do with simple tuning and deleting emissions. If HHO is actually doing anything anywhere it is only because it is fooling the tune and changing power and emissions not efficiency.

I do say try it on a couple of trucks with long established routes and drivers. Don't tell the drivers anything is changed and see what you get if they will give you your money back.

[craysus]

Not a bad paper..

https://www.tc.gc.ca/media/documents...T-MAY_2012.pdf

[ThermionicScott]

I wonder how hard it would be to make an accordion connection between the cab and trailer, like you see in articulated buses. Even though the airflow would still be pretty dirty around those folds, the majority of it would have to flow around the whole thing as a unit rather than detaching and swirling around before hitting the square front edge of the trailer.

If there's one thing I've learned on EcoModder, it's that even when a vehicle company tries to make something reasonably aerodynamic, there are still lots of opportunities if you're willing to put some work into it.

[craysus]

There are some adjustable gap devices out there, but most seem prone to failure fairly quickly..especially when you change trailers frequently..you never know what the next trailer will be exactly..

Further, with refrigerated trailers, you need to feed the fridge motor some air..

I am studying as much as I can on the Vortex generators (twin closed vortex scrolls style.. (Kinda of a V shaped bit of plastic).) not sold on them 100%, however we have some in use already and they definitely keep the rear doors cleaner on the trailers their installed on currently.

We have not put them on the rear of the truck, or on the gap between trailers yet...merely on the back of the last trailer..I am now looking to get some of these at a reasonable price instead of the absolute rip off $5+ each they charge us from the suppliers currently!. As I will need around 18000 of them, thats a considerable chunk of change, so will approach some manufacturers to reproduce at a more realistic price..
They are on the market from multiple vendors, and are all basically identical (Small size changes, some have a strip with 4-5 of them, instead of single units etc..). Having had some car parts produced previously myself (Predominantly carbon fibre air intake systems for a sports car..and engine mounts for the same sports car) I am not worried in contacting people to get mass production at a reasonable price..
5 cents worth of plastic and glue should NOT be sold for $5...

[freebeard]

If you're installing 18,000 of them; it might be worth investing in some Computational
Fluid Dynamic simulations.