Came across the following post by a Allison tech, and it reminded me that since I do not have service history on my trans to possibly do a trans fluid drain and swap to synthetic. All input from you is appreciated, my rv has approx 1997 3060R has105 K miles. "yup, you just drain what will come out of the sump. the torque converters do not have a drain plug like some other transmissions do. the synthetic fluid will mix but after changing to synthetic you have to follow the non-synthetic fluid/filter change interval one more time (15,000 for filters and 50,000 for fluid). after the 2nd fluid/filter change with transynd, you can follow the synthetic drain interval (25,000 for filters and 100,000 on the oil). make sure you use Allison filters, some of the other filter manufacturers claim they filter smaller microns of particles (and they probably do). this means they will clog faster and need changed more. you don't save any money because your changing a cheaper filter more often than the proper one"
Jack,
Nobody here will argue against using a synthetic, although some (like me) may not agree that swapping to synthetic (in older transmissions like mine) is necessarily mandatory. My just saying that will probably raise a firestorm of heated rebuttals. No matter - I'm fireproof.
The following post may be pertinent to your question:
transmission oil (http://www.foreforums.com/index.php?topic=30583.msg265579#msg265579)
I agree with Chuck, nothing says you must use synthetic fluid. Our motor homes are light duty in the transmission world, compared to dump trucks and garbage trucks. The most important thing is follow the recommended service instructions for the fluid you use.
And Allison would argue with "RV's are all considered light duty". The TRANSMISSION RETARDER throws the Foretravel into the heavy duty category.
With cost of fluid vs transmission, I am a strong believer in Transynd and the heavy duty schedule for retarder-equipped coaches.
My 03 came from the factory with Transynd.
I had my transmission fluid changed at the regional Allison Service Center near here. Transynd was not much more exprensive than organic fluid. About the same advice for a coach with a retarder, change fluid and filters again in 12,500 miles and the filters at 12,500 mile intervals and fluid at 125,000 or four years. So it is about every two years on the filters and every four on the fluid for me. I like to do all of this service as well as oil changes and other regular service in the late fall when the coach is going to sit for a few months (other than its once a month warm up run) before heading for warm.
Transynd handles the extra heat from the retarder better than organic fluid. A good reason to switch if you have a retarder.
ALL Allison trannys with retarder will benefit from Synthetic. It is the higher heat that degrades non-synthetic. And all transmissions really work hard and all will be happier with synthetic. Sort of pay now or pay latter. I am a believer that synthetic in transmission extend our fluid change duration, but the same does not hold for engines where even synthetic should be changed at the same interval as non-engine synthetic fluids. So there is a measurable payback with tranny synthetic, but not engines.
Changed my synthetic oil after running 22,000 miles and took oil sample,the sample came back good to go,so in my opionion
synthetic oil in an engine is well worth it.
Trans filters every 12.5K? Having trouble seeing why this would be necessary. Closed system, no combustion products, careful mgmt of heat during retarder usage, no air circulation thru system. Are these exceedingly poor quality filters that rapidly degenerate?
I've never seen an Allison publication recommending filter changes more frequent than oil changes. I've been changing both at 75,000 miles but disregarding the 48 month limit agreeing with Chuck's philosophy.
Allison considers a transmission with a retarder in severe service. I am nice to mine and watch retarder temps carefully. I will change filters every two years. At four years I will probably send in a fluid sample and see. The late Dave M still reminds us, "Do what makes you happy". Happy Holidays to my old friend.
I agree with Brett on what Allison says. However common since needs to apply here if you leave your retarder on the majority of the time then yes, if you use your retarder sparingly and watch temps closely then that's another story. Also unless something is wrong filters should last way more than 12K. JMHO.
We completed a trip to Alaska this year so alot of mountain driving.Used the retarder basically all the time,my trans temps never
got to more then 225 degrees,BUT I have the rocker switch not the joystick.In following the posts thru the years I think the
coaches with only the rocker have cooler retarder temps.The reason being for me to get to the 2nd and 3rd retarder positions I
HAVE to use the brake pretty hard.With the joystick you can push the retarder harder and get higher temps,just my opionion.
Possibly less heat generated by not having (or using) the joystick, since as you say, you have to apply the brakes pretty hard to activate maximum retarder braking. However, unless you can actually monitor the retarder temperatures, you can't really know how much heat stress the trans fluid is exposed too. It takes extensive use of the retarder over long periods to have the increased temperatures of retarder use show up in the trans temperature dash gauge. Or said another way, using the transmission retarder for a period of time will raise the transmission temperature readings as the fluid from the retarder accumulator mixes with the trans fluid in the other areas. With the VMSPC, you can see the retarder accumulator temperatures change nearly instantaneously. Gradually, the transmission temperature gauge will rise as the accumulator fluid mixes, but the retarder temps can rise to 300º and more without showing much of a rise. After not using the retarder for a time, the temperatures equalize and then gradually return to normal without further use of the retarder. For me, I use the VMSPC reading to choose the optimal mix of gearing down and retarder joystick setting to manage the retarder temperature. If you just pull back on the joystick without gearing down, the temperature can quickly rise on steep downgrades. Gearing down and having the joystick back to about the second or third notch will generally hold the speed down to the desired level with temperature stabilizing at well less than 300º (usually less than 250º) without touching the service brakes. I do use the max retarder when needing to shed a lot of speed quickly, but this is of very short duration and the temperature rise is brief and rarely approaches 250º and only very briefly at that.
Fortunately, service records I have shows that the original owner of our coach had Transynd put in early on and I have since changed the fluid and filters using Transynd, so I feel like the transmission has been well cared for before and since our ownership. I like the safety margin the higher heat tolerance that Transynd provides over conventional fluid.
Don
No vspc on ours(too old) but my gauge is pretty quick to show heat and show cooling temps.
I like John44 change engine filters between 15k and 20k depending on the time frame. My test results come back showing the oil is good for a lot more miles but it gives me something to do by changing them!!! I also, like John44, use Amsoil in all areas and believe it is superior to all the other oil manufacturers that followed years later switching over to Syn.
The Allison loves the Torque Drive I use even though it is said to NOT use it. No clunking in my Tranny.
Luv it
JohnH ^.^d
I'm not familiar with Allisons. She's got 13k since a Transynd oil & filter, changed in 11-2011. Any thoughts when I should be thinking "next"? Thanks, ^.^d
When I drained the 19 year old factory fill (filters stamped 94) and refilled with Transynd I noticed an immediate improvement in cold shifts. It was slightly lazy with the shifts when cold and now is as crisp and quick pulling out of the driveway as it is at full temp after an hour on the road.
I would use nothing else, just for the peace of mind knowing I have the best Fluid in.
Mike,
You are more likely to change on "time" than miles. The fluid is now 6 years old (but only 13k miles).
As with many RV's, the issue is "cost of fluid and filter change" vs transmission overhaul/replacement.
I have always erred on the side of "fluid and filters are a lot cheaper than transmissions".
We get the clunk once in a while,seems like it will do it under low/partial throttle.
Re: to get to the 2nd and 3rd retarder positions I HAVE to use the brake pretty hard
I thought the three air pressure retarder switches close with pressures like 2, 4, 6 PSI or some similar very low PSI's. This would bring full retard for most stops.
Adding a joy-stick is very straight forward and user installable, mount joy stick & plug in a 3-way cord. Joy sticks are very valuable, keeping foot off brakes allowing the air brake system and retarder to operate separately and offer much safer redundancy. Also the joy stick cost may offset replacing brake pads in the future.
Agree,my main point was that the joystick type sees more heat than the rocker switch type.
Thanks, Brett. I know you have been on me to follow the "six year rule" for other fluids, so I'll add the transmission when I have the LOF done come spring. The nice thing about the shop I'm going to in Tucson is they are not only a Allison factory outlet, but CAT, as well. If they can do the two and the air dryer quickly, I'll be happy, we hate sitting in waiting rooms or overnighting!
Mike,
You can help insure a "clean job" by cleaning the bottom of the transmission, particularly around the drain plug and two filter caps. An old kitchen brush Dawn and water work just fine. Many techs do not take the time to clean before opening the transmission.
And, cheapest way to buy Transynd is to buy a 5 gallon pail (a very common Allison PN). Pick up an old one gallon Transynd jug (plenty lying around any Allison shop) and pour 1 quart into it. Then the 19 quarts left in the pail is the proper change quantity for your transmission.
With my bad back and sharp gravel site, I can't get under, but will save your post for when I go in for service. Thanks, again. M b^.^d
Don my trans warning buzzer comes on at 250 on Vpms
Bob, mine comes on at 250º, but that is on the dash gauge. The VMSPC retarder temperature gauge would have been up close to 300º or just above by then and averaging in the mid to high 200º's for awhile as in going down a long steep grade for awhile without downshifting at the 4th or 5th notch. I also have the trans temperature on a VMSPC gauge that corresponds to the dash gauge, but that is not the retarder fluid sensor, it is reading the trans fluid temperature in the sump.
Don