Preventive Maintenance Intervals for Transit Buses (2010)

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48 SYNTHESIS QUESTIONNAIRE PREVENTIVE MAINTENANCE INTERVALS FOR TRANSIT BUSES Total number of agency responses: 38 Transit System Characteristics: 1. How many total buses are currently operating in your fleet? Total Diesel 9,457 Total CNG 1,669 Total Hybrid 434 Total Gas 257 Electric 226 LPG 19 Total Survey Fleet 12,062 2. What is the total annual miles traveled (approx.) for the combined bus fleet? Total 30-foot & Over Annual Fleet Mileage 464,755,387 Total Under 30-foot Annual Fleet Mileage 30,511,782 Total Annual Fleet Mileage 503,364,369 PM Classifications 3. Which of the following maintenance activities are scheduled according to an established interval? Examples of intervals include mileage, time, hours, season, etc. PM Inspections Service Line Inspection Daily: 88% Other: 12% Bus PM Inspection (PMI) 6,000 Miles: 71% 2,000–6,000 miles: 92% 6,500–7,500 miles: 8% Other PM Inspections HVAC: 6,000 miles: 33% Annually: 20% Twice a Year: 13% Lift/Ramp Inspection: 6,000 miles: 47% Within 7,500 miles: 63% Driver Inspection: Daily: 100% Multiple Daily Inspections: 9% Do you use different PMI intervals for other buses in your fleet? YES: 57% NO: 43% If yes, explain: The primary reason given for conducting more frequent inspections, in the 3,000–4,000 mile range, pertain to hybrid buses (one response); and those operating smaller paratransit vehicles (10 responses) and buses with engines fitted with exhaust gas recirculation (EGR) (three responses), both of which require more frequent oil change intervals. PM Repairs Only list those repair activities done as a preventive measure based on time, mileage, or other condition, not because of failure. Agency responses were varied and somewhat difficult to classify. Except for oil/fluid and related filter changes, repair activities done as preventive measures drew assorted responses. Air system servicing was reported by six agencies with differing intervals: 24,000 miles, 48,000 miles, 60,000 miles, annually, twice per year, and 1–2 years. APPENDIX B Survey with Summarized Responses

49 PM Overhauls/Refurbish Only list those overhaul/refurbish activities done as a preventive measure based on time, mileage or other condition, not because of failure. Agencies responded in six categories. Four responders rebuild engines in full-size buses (35 ft and larger) at 300,000 miles; two perform the rebuilds at about 450,000 miles. One agency replaces DDC S50 engines at 350,000 miles, Cummins ISC engines at 375–400,000 miles, and Cummins ISB engines at about 250,000 miles. Establishing PM Intervals 4. What method do you use to make sure PM intervals are conducted on schedule? Computer Based Program: 100% Computer Based Plus Excel Spreadsheet: 8% Computer Based Program Plus Manual Books: 3% 5. What interval “window” do you use to determine if PMs are done on schedule? 10% of mileage/hours: 42% Not Tracked: 5% Other: 53%, Explain: 65% of these use some type of mileage-based system 6. If you use a computer based software program to establish PM intervals, is it flexible enough to allow you to make changes? YES: 82% NO: 8% NA: 10%, Intervals are set by people, or manufacturer recommendation 6a. Are you pleased with the software program used? YES: 56% NO: 24% NA: 20% What is the name of the program used? Thirty-eight responding agencies report using twenty-two different computer based programs to track PM intervals. 7. If you use a computer based software program to establish PM intervals, is it also used to guide and track the actual PM activities (repairs made, parts used, etc.)? YES: 87% NO: 3% NA: 10% 8. Are PM intervals based on fixed points (i.e., every 6,000 miles, every 30 days, etc.) or are they re-set based on the last actual interval (i.e., if the first PM was conducted at 6,300 miles then next one is scheduled for 12,300). Fixed Point Interval: 39% Re-set Based on Previous Interval: 61% 9. Which manufacturer (OEM) recommendations most influence the setting of PM intervals? (Check all that apply and include the interval.) Responses are summarized in chapter three, Table 8. 9a. Do OEM warranties influence the setting of PM intervals? YES: 74% NO: 26% If yes, explain how: Responses are summarized under Influence of OEM Warranty Coverage in chapter three. 9b. Do you change your PM intervals after an OEM warranty has expired? YES: 18% NO: 82% If yes, explain the activity and why it’s changed: Responses are summarized under Influence of OEM Warranty Coverage in chapter three. 10. What specific PM activities have been put in place because of data/information made available to you from road call reports, driver pre/post trip reports, service line inspections and other sources? (List all that apply and include the interval. Read questions 11–13 before answering.) Responses are summarized in chapter three, Table 9. 11. What specific PM activities have been put in place because of unique environmental conditions such as extreme heat, cold, humidity, winter salt use, and other environmental factors? (List all that apply and include the interval.) Responses are summarized in chapter three, Table 10.

50 12. What specific PM activities have been put in place because of unique operating conditions such as duty cycle, terrain, road conditions, and other such factors? (List all that apply and include the interval.) Responses are summarized in chapter three, Table 11. 13. Which PM activities have been put in place because of your agency’s fleet make-up (diesel, CNG, paratransit, etc.)? (List all that apply and include the interval.) Responses are summarized in chapter three, Table 12. 14. List any unique or innovative approaches you use to establish PM intervals. Responses are summarized under Innovative Approaches to Establishing Preventive Maintenance Intervals in chapter three. 15. What information, tools or additional resources would help you do a better job to establish PM intervals? – Sharing of agency PM information regarding emissions, engines and transmissions. – Examples of other transit PM schedules. – Recommended life expectancy of equipment. – More precise presentation of PM information from manufacturers such as comprehensive PM tables. The most difficult part of establishing a PM program is gathering up all of the requirements that the manufacturers have hidden throughout the manuals (3 responses). – Good supervision and well trained personnel (2 responses) – More reasonable PM schedules and recommendations from the OEMs. Most are reasonable, but sometimes you can detect a few unreasonable intervals that are probably designed to “cover” the OEM or component manufacturer. – More staff and resources to analyze data, failure trends, times, etc. (6 responses) – Software to track actual idle time to achieve a more precise accountability of both engine and transmission life cycles. – A dedicated quality assurance section to analyze failures and recommend updates to preventive maintenance procedures. Conducting PM Activities 16. Once PM intervals are established, do you use a checklist to guide your PM activities? YES: 100% NO: 0% If yes, check all PM activities below where a checklist is used. Also indicate if the checklist is generic in that it applies universally to all applications, or if the checklist is unique in that it applies to specific equipment. Responses are summarized under Checklists in chapter four. Also see Table 13. 17. Do you provide technicians with written instructions to help them carry out PM inspections and activities? YES: 79% NO: 21% If yes, list those PM activities where instructions are provided: Responses are summarized under Written Job Instructions in chapter four. 18. Do you provide specific pass/fail criteria for carrying out PM inspections and repairs (i.e., front brake throw 2.0″ max)? YES: 84% NO: 16% If yes, list those PM activities where pass/fail criteria are provided (or attach PM checklist showing all criteria): Responses are summarized under Pass/Fail Criteria in chapter four. 19. What is the skill level of personnel carrying out PM inspections? Skilled: 60% Entry-Level: 16% Other, List: 24% (1 journey level, 1 use both, 1 must have two years experience, 1 trains with skill tech.) Explain why you use particular skill levels for carrying out PM activities: Responses are summarized under Skilled vs. Entry-Level in chapter four. 20. Do you use the same person to conduct all aspects of the PM activity or do you split responsibilities between routine tasks (i.e., change oil, check tire pressure, etc.) and more demanding tasks (adjust brakes, etc.)? Same technician does it all: 61% Split PM responsibilities: 39% Explain why you use one approach over the other: Responses are summarized under Splitting Work Responsibilities in chapter four.

51 21. Are there any work rules at your agency that influence the type of skilled technician allowed to conduct PM activities? YES: 39% NO: 61% If yes, describe them: Responses are summarized under Work Rules & Standards in chapter four. 22. Have you calculated the amount of time needed to conduct PM activities? YES: 74% NO: 26% If yes, indicate your findings in terms of hours needed to conduct each PM activity. Responses are summarized in chapter four, Table 14. 23. Have you calculated the number of spare vehicles needed to conduct your overall PM program? YES: 50% NO: 50% If yes, indicate your findings regarding the number of spares in terms of percentage of the overall fleet needed to conduct your PM program. Responses are summarized under Bus Spare Ratio in chapter four. 24. Have you calculated the cost of conducting PM activities in terms of combined parts and labor? YES: 63% NO: 37% If yes, indicate the cost in dollars (parts and labor total) to conduct specific PM activities. Responses are summarized in chapter four, Table 15. 25. Before beginning a PMI do you issue a work order that generates a parts kit containing all parts needed for the particular PM activity? YES: 51% NO: 49% 26. Do you have any quality assurance measures in place to follow-up on PM activities? YES: 79% NO: 21% If yes, describe those measures. Responses are summarized under Quality Assurance Procedures in chapter four. 27. When it comes to PM inspections, indicate the policy you use to repair defects found during the inspection process. Describe other repair policies: Responses are summarized under Repair of Noted Defects in chapter four. If you schedule repairs for a later date how do you track completion? Responses are summarized under Repair of Noted Defects in chapter four. 28. What specific aspects of PM intervals would you like this Synthesis Report to address? – I would appreciate a movement to standardize information from manufacturers. It is very difficult to bring all of the pieces together if they are allowed to continue to hide or bury PMI and servicing information and intervals throughout manuals. – Issues with certain types of vehicles/equipment – Rationale for PM intervals – Hybrid PM programs – Would like to see examples of check off sheets and SOPs Policy Response All defects are immediately repaired unless parts are not available. 46% All defects that can be repaired in a given amount of time (1 hour, up to 2 hours, and 3 hours) are repaired; all others are scheduled. 8% All defects are scheduled for repair at a later time. 11% Other 35%

– Costs and how PMI identified defects are addressed – What are safe intervals. – I expect basic bus PM intervals will be a moving target because so many agencies have various types of equipment and operating conditions. I think that emphasis on the more sophisticated components and systems—emissions systems, multi- plex, etc., may warrant some attention in the report. Of particular interest are the 2007–2010 engine emission systems, hybrids, PM intervals on technology systems (AVL, video, and other information systems) that the fleet shop may not be prepared to PM and repair but PM and repairs are required. As buses become increasingly more technologically advanced there will no doubt be additional systems to address during the periodic PM. Who should do it? – Time study? – HVAC is the standard Thermo King inspection forms. Our bus PM forms are split between large bus, small bus, and ser- vice vehicles. The series of forms for each vehicle type are mostly generic with specific references to a unique component due to bus/vehicle type if applicable. Since we are pretty much 90% New Flyer and 100% Champion this becomes less of an issue and we try to maintain commonality of components within the fleet between build years if at all possible. We are in the process of updating our forms as we’ve added articulated buses. We are also cleaning up to remove past references to past model bus components no longer in use. We are going to go with an electronic PM inspection form as part of this update process. From that point updating the form becomes very easy when required due to the introduction of new components or bus types. – That each fleet type and make or model can affect what items are addressed on a PM inspection. PM checklists should differ as do vehicles being inspected. – I would also like to see that the report addresses changing and evolving technology that vehicles have, increased skill sets needed to perform PM inspections and the amount of labor time to do the PMI is also increasing with additional technologies. – Although I don’t track it I am interested in time information. Also just general intervals for all the sub systems will be useful. Also if anyone has information on going away from the standard 6,000 mile interval showing that you can save money and still have a dependable fleet would be interesting. – Time standards for specific tasks – Extended intervals, what has worked and what has not – Calculating intervals using vehicle performance as a factor – Estimated times, confirmation of correct intervals, inspection process; i.e., who inspects, who lubes, who does repairs, how shop is laid out, etc., who’s not using paper; i.e., all electronic data entry at mechanic level; i.e. hand helds. – PM Best Management Practices – Peer Reviews of PM Programs – I’m looking for something someone else has thought of that I have missed. – If cost savings can be achieved though different methodologies. Also, if there is a recommended review and quality assur- ance process that could be used as a guideline or template for establishing intervals (if it could only be that easy . . .) – Areas and ideas for improvement – Stay on top of things the best you can – Should the schedule PMI be shortened or lengthened. Please add anything else you feel would benefit your peers with regard to PM intervals. – PMs are scheduled on a 6,000 mile cycle. Each PM occurs every 6,000 miles. Specific system inspections are conducted as part of PMs labeled “PM (interval)” and “INSP (interval),” calculations of labor hours and total costs include the specific system inspections for the appropriate interval. – A discussion of synthetic versus conventional oils and lubricants. Comparisons of PMIs relative to operating costs per mile, engine/trans life, bus changes. I know our program is improving based on internal performance reports. However, I’m not exactly sure where to set realistic goals. At this point, I’m pushing reductions in bus changes and improved vehicle availability while staying within budget. How we compare to other agencies however is not clear. – Any cost savings – The one thing that I really had to get a handle on was getting all of the technicians on the same page as far as inspection and repair criteria for safety-sensitive systems. The checklists have the same checks, but how the technician determines if a component or system is serviceable and safe was all over the map. To help resolve the inconsistencies that I was find- ing in how different techs inspected everything I designed an in-house certification program that included over 70 specific inspections and tasks that everyone was trained to perform the same way and to the same standard. This has worked well for our shop. It establishes inspection and repair standards and removes any ambiguity when performing inspections. – The items listed below are intended to become part of the PM process at some time in the future: Legacy PM items with increased frequency due to other factors: Batteries—Increased electrical load Differential—Hybrid Bus—Increased wear due to increased torque Air Compressor—Replaced based on predictive analysis Brakes—Hybrid Bus—Additional lubrication requirements due to extended brake life. 52

53 New PM items due to the introduction of new equipment. It is intended to PM the listed items 2 ×’s per year addressing all listed items at the same inspection: Destination Signs Farebox Camera Video Automatic Voice Annunciation Automatic Passenger Counting The hybrid drivetrain presently installed on 43 buses is currently being integrated into the PM program. – PMI checklists should be specific for the fleet they are created for and the checklist should be dynamic and change as needed to reflect items that are determined to be high maintenance or that have higher failure rates. Smaller agencies should work with OEMs and larger agencies. – Intervals are being extended by OEMs because of better vehicles, parts and the oil we use. For example we recently ordered several Sprinter vans and they have a oil change interval recommended be the OEM of 10,000 miles. – Safety first—so a good PM program with Master Technicians is a must for public safety and extending equipment life. Our families and friends are on the buses we maintain and travel the same streets as our buses so we can never be too safety minded. – The county transit agency has adopted a PM program based on conducting two (2) inspections. The mileage intervals for these PMs are as follows: PM “A” every 6K miles and PM “O” every 3K miles. – I feel that the sharing of information is an important part of establishing a comprehensive maintenance program. Coming from a transit maintenance organization that does not have a dedicated staff for writing preventive maintenance proce- dures, I try to get copies of other properties’ maintenance programs and incorporate some of their practices into our preventive maintenance program.