User Rating: 0 / 5
One of our client fleets was considering the elimination of their “dry” PM Service. They would move to performing an oil drain PM service at 35,000 miles. They had a concern with the fuel filters, specifically if there would be a significant drop-off in fuel pressure and also whether their MPG might be affected by leaving the fuel filters on for 35,000 miles versus 17,500 miles. To assist this fleet with their decision, we asked our roundtable members about their experiences with longer oil drain intervals, and specifically the effects on fuel filters and consumption. Here is their feedback:
- We have trucks set at a service interval of 40,000 miles. Oil and fuel filters seem to be holding up fine
- Fuel economy is right near our Freightliner EVO’s with DD15’s. Not seeing drop off of fuel economy
- Only thing we would say is not sure the chassis is going to hold up to those intervals. Will have
to watch the RO’s without PM’s as they get older
- We are currently running multiple service intervals: 25000 grease/50000 oil. Fuel filters being changed at both because of performance issues
- Chassis grease was almost always our limiting factor with PM intervals
- Our fuel filters held up fine in the 35,000 mile range and of course many times when we were over the mileage deadline. We ran some out in the 45K range with no noticeable drop in fuel economy or other issues
- We have 945 engines, DDC, Cummins, and MaxForce on 50 K intervals. Our 12 month trailing average of pre-mature fuel/water separator replacements is 39 per month and it is trending down significantly. It will increase during colder months
- We can’t verify there is any drop off in fuel economy or pressure. Performance can be affected and that is when we start looking at the fuel filters
- We have found the quality of the filter to be very important. We are currently using lube-finer and have no major complaints. They are holding up well while some other brands in our past have not
Are your experiences with oil drain intervals, fuel economy and overall performance consistent with these comments?
Would you like to add anything to the discussion or get feedback on another area?
User Rating: 0 / 5
- Diesel engines v. CNG/LNG engines
- Steel wheels v. Aluminum wheels
There is a considerable amount of buzz in the Class 8 tractor markets surrounding the use of Compressed Natural Gas (CNG) and Liquefied Natural Gas (LNG) engines in over-the-road fleets. As more fleets convert or test this new technology, we began receiving questions about the cost difference in maintaining these engines versus the standard diesel engines. In discussions with our roundtable members, we discovered that we are very early in the data collection process for maintenance costs relating to these options. But, we did receive some feedback. Here is a sampling of the information that was shared:
- We have run a few test trucks for less than a week at a time.
- We have talked to some of the people at a private fleet. They said their maintenance costs were $.03 to .04/ mile higher. They have many driver complaints due to power loss, because they went to smaller engines.
- The big thing that I am hearing is the downtime issues getting replacement parts and qualified techs to work on the equipment. Also, shop upgrades to handle CNG equipment
- Must consider upgrading shop buildings to meet local fire marshal requirements
Within our six roundtable representatives, and the 6,500 tractors they have on the road, there are very few CNG or LNG units being operated. We will have to wait for longer operational periods with this equipment to get more reliable data.
On our second topic, one of our members was inquiring about – “Have you ever found that there was a ROI (Return on Investment) involving the use of aluminum wheels?" Our members weighed in with the following feedback:
- The only payback I have found from aluminum wheels is weight savings for weight sensitive fleets. I know the marketing on these wheels outline many other benefits, including driver retention from the “bling” factor, but I have not been able to quantify other paybacks
- We can’t document the ROI, but trade value is increased. The dealer claims between $1,200 and $1,500
- We are hauling a couple of hundred pounds around in tare weight so it has to save a little fuel
- Mount/dismount is being out-sourced which costs more and if you have to replace a wheel; the cost is significantly more than replacing a steel wheel.
- We doubt the extra cost outweighs the increase in trade value, but the truck looks better with aluminum
One of the interesting points made within this topic - We have to look at all options for getting a return on our investment.
Do you have any experience with these two areas that you would like to share?
User Rating: 0 / 5
Air Ride versus Spring suspension – What are fleets spec’ing and why?
Toward the end of the year, roundtable topics usually begin to center around decisions relating to how to spec equipment. As the fleets represented by the roundtable begin these exercises, they find it useful to solicit experiences from other fleets with spec’ing different components or systems. The roundtable becomes an important tool for them to surface topics for input from other industry contacts in the fleet maintenance world.
Recently, one of our members was trying to decide whether to spec future trailers with air ride suspensions. They also wanted to know, if the other members had transitioned away from air ride, have they been receiving driver complaints.
We presented the following question to the group - “Are you spec'ing trailers with air ride or spring suspensions? If you are spec'ing spring suspensions and have previously used air ride, have you heard any issues from drivers - Extra "jumpiness", drag/pull issues or anything else that affects the ride in the cab? ”
We received the following feedback:
- We have been converting fleet to spring ride since 2010, lower maintenance costs both In-House and Breakdowns
- Reduced inventory costs by not spec’ing both
- All spring ride since 2008
- No driver or customer complaints
- Reduced maintenance cost with spring
- No dock walking issues
- We are 100% spring ride now
- No issues with drivers or customers
- We are seeing a decrease in maintenance on the dock bumpers at our service centers with the spring ride
- Spring ride does not move as much during loading/unloading
- We have spec’d spring ride for the past several years
- No extra jumpiness that we know of
- Some customers are asking for air ride, few demand it
So, to summarize what we heard – Fleets appear to be shifting away from air ride suspensions (if our roundtable representatives are an indication of the marketplace), and driver issues have been minimal. There appears to be added benefits with maintenance costs and repair occurrences.
Have your experiences with air ride and spring suspensions been any different?
User Rating: 0 / 5
Auxiliary Power Units
Dealing with driver concerns that the APU does not properly cool the cab
Continuing our series on roundtable topics, we recently were asked by one of our members to poll the other members to determine whether any of them were dealing with complaints from drivers about the ability of their APU’s to properly cool the cab. We knew that this issue was surfaced by a company that had a majority of their fleet operating in the south.
So, we circulated this topic and received some very valuable feedback on operation on the APU’s. Here is a sampling of their comments:
- That is a very common complaint with different APU’s. We have run many other (than TriPac) APU units since 2002. It really comes down to Air flow and, the older the unit gets the worse the issue becomes. We airflow test all of our APU’s (periodically).
- One other thing to look at is the spec of the equipment. You can order double insulation or extreme weather packages from the manufacturers when specing the trucks.
- The main issue that we encounter with our APU’s is the driver wants to cool the entire cab. We are educating the driver to close the bunk curtains when the APU is in use.
- We not only encourage our drivers to close the bunk curtains but to also pre cool the sleeper berth.
In addition to this issue with cooling from APU’s, we have also worked with fleets that have seen a significant spike in APU costs as the units’ age beyond three years. In some cases, we have client fleets with their APU cost per mile (CPM) reaching levels that compare to their tire CPM. We believe that with the right combination of education to the drivers, and maintenance program for the APU’s, fleets can manage this cost to within reasonable levels and limit driver issues.
We encourage fleets to attempt to “marry up” the APU PM Service with the tractor PM Service to reduce shop visits between PM’s. Furthermore, we believe it makes sense to establish PM intervals using APU engine hours versus a specified period of time. During the spring and fall seasons, the units are operated less frequently and can therefore allow you to stretch PM service intervals and save money on material costs (oil and filters).
We are interested to hear from our Huddle members on their experiences with APU’s. Any feedback on:
- Cooling capability?
- PM Services?
- Overall costs?
We also would like to thank two of our roundtable members for their contribution of guest articles to the Huddle in the past – David Graham, VP of Maintenance at PTL (Paschall Truck Lines) and Phill Reynolds, VP of Maintenance at Transport America.
User Rating: 0 / 5
Master Fleet Roundtable Discussions
As we have mentioned in previous articles, we have had the good fortune of having a group of fleet maintenance professionals that have agreed to share thoughts, experiences and ideas relating to the maintenance of transportation fleets. Our roundtable group is made up of 6 members that hold positions ranging from VP to Director of Maintenance. This group of professionals is responsible for the maintenance of 6,500 tractors and over 20,000 trailers and they have combined experience of over 80 years in the transportation industry. As issues, concerns or questions arise, they forward them to Master Fleet and we circulate them to the other members. The roundtable group replies to all the other members with their thoughts, suggestions or ideas. We have learned so much from this group and the members have the benefit of learning from each other. Since all the topics are current concerns or needs, we’ve decided to run a series of five articles recapping recent discussions within this group.
The first one deals with a recent test performed at a roadside DOT inspection – PBBT:
In case you are unaware, PBBT stands for Performance Based Brake Test. The PBBT is a roller dynamometer which measures the tractor’s brake force and calculates brake efficiency to indicate the effectiveness of the vehicle’s brakes. Not all states have or use this technology to test Class 8 tractor/trailer combination braking systems. In fact, within our roundtable group there were members that had not encountered DOT violations relating to this test. There is no special preparation that a fleet can do to ensure satisfactory results from this type of testing. Follow proper maintenance practices to keep all braking systems in good working order. Areas of the braking system to inspect and maintain:
- Brake lining thickness within DOT specifications and consistent with manufacturer recommendations
- Airlines free of any defects such as chaffing
- Proper operation of brake chambers, S-cams and slack adjusters
- Brakes properly adjusted to ensure most effective operation and braking power
- Brake drum condition consistent with DOT and OEM specifications
- All brake pedal linkage in proper working order
These bullet points only represent some of the more common issues to address. As fleet maintenance professionals, you must also utilize proper pull standards for brake linings and drums and audit your technicians to ensure compliance with standards.
We would like to close our article this week with a special thank you to all our roundtable members. We appreciate their willingness to be involved in this group. It is our sincere hope that they get just as much out of their participation as what they put into it.
In the coming weeks we will provide insight into fuel filter replacement intervals, air ride versus spring suspension, the difference in maintenance costs between diesel and compressed natural gas and performance expectations from auxiliary power units.
Like us on Facebook
We have 8 guests and no members online