Topic: Allison Transmissions (Aug 2001)
Presenter:
Note Allison has revised the service (fluid change) interval for its World transmissions.For a new unit the first service is 5,000 for filters only -- but he recommends changing over to synthetic oils at that point. Thereafter it's 25K miles or one year for both oil and fluid changes -- unless you're using synthetic. Present oil choices are Dextron III, or Castrol product called TranSynd. It's marketed through Allison centers, and it's about $7/qt. Once you change to TranSynd, the service interval becomes 50K miles or two years. At that point need to change filters only. Then another 2 yrs/50K miles before do the change filters and oil. Thus it's 100K or 4 yrs between transmission oil change with the synthetic. Note that although other synthetics (e.g. MobilOne) claim 100,000 miles change interval, Allison will ONLY honor an oil related failure if the synthetic used is its own TranSynd.
Q: Do they put synthetic in new coaches? A: Not yet., but in the future all new units may come from the factory with synthetic.
Normal operating temperture is 200 degrees at 50 mph. One RVer noted his Silverleaf is showing 160, and is measured from the sump. That's a good cooling package. On the dash guage the analogue guage will be reading perhaps 40 degrees higher, since it measures the fluid at the hottest point.
One year interval is because sitting around and not using the oil is harder on it than when it is in frequent use.
Lots of information available at http://www.allisontransmission.com
Note: There is a free videotape (18 mins) on the use of the Allison World transmission for motorhomes. Call Allison, toll free, at 1-888/666-5799. The video is identified as "V13424EN".
The downshift from 5 to 4 is the roughest point. It can be recalibrated, but needs to be done at an Allison shop. It takes about an hour, and is covered by warranty.
When you first start each day, the low oil viscosity causes the first shifts to be quite rough. After about 25 miles this roughness will go away.
Any analogue guage will be most accurate at "mid range" measurements.. At the extremes, it is much less precise than a digital guage.
Economy and Performance modes: The economy mode simply means the shift point will be two miles per hour later. Not for use in traffic or hilly terrain.
Cummins position on Gale Banks: They make some good quality products that Increase fuel pressures, fuel flows, reduce exhaust pressure, increase air flow. A Banks installation won't de facto void your warranty. But: Banks equipment increases engine heat and doesn't increase cooling ability. If an engine failure is the result of over heating, Cummins will not honor it as a warranty item, and "from what I've heard" Banks won't cover it either.
Use of engine chips: If an engine failures result from increase in horsepower, Cummins won't honor claim.
Cummins 300 or 330 can be increased to 350 by Cummins. But 350 is the tops. The 370 will likely be upgradeable to 400.
To check transmission fluid level: Simultaneiously press up and down arrow keys. Check oil when rig is warm, before shutting it off, and it will give you normal or how many quarts low.
Keypad on world transmission has the ability to check five codes identifying problems.
When climbing a steep hill, you'll get a downshift 200 rpm sooner with a manual downshift than if you use only the throttle.
Exhaust brake -- you can use it at any speed. Internal fail-safe mechanisms will preclude any engine overspeed.
If you press drive and it blinks at you, the rpm is too high. If it's over 900 rpm, it won't go in gear. The same is true at -25 degrees.
Parking -- going from drive to reverse and back as you navigate into a space. You can reduce "shift shock" by going through neutral; a lesser but helpful option is to keep foot on brake when you shift between forward and reverse to avoid drive shaft motion contributing to the shift shock.