Allison Transmission Leaks

Beethovin · 08-25-2008, 01:05 PM

There are times when I really would like to reach out and touch someone at Winnebago, GRR!
We bought a new Adventurer LT on July 3, 08 with the new Workhorse UFO gas pusher chassis. Aside from the normal and frustrating minor problems at delivery we were on our way in short order. After one return trip to the dealer for some service problems we set off for Duluth MN. On our way I discovered a transmission oil leak (oil all over the front of our Toad). Called our dealer and found we had to contact Workhorse for chassis service. (I wonder how Winnebago handles Michigan Lemon Law issues?) Called Workhorse and was referred to a truck service facility in Superior WI. Talked to the technician who worked on the problem. He claimed the oil pan gasket was leaking. I am a retired mechanic so I had a look but didn't see anything. Anyway, no disputes, just replaced the seal and on our way. 177 miles later in St Cloud MN the same problem showed up (oil all over the front of our Toad). Crawled under and checked the leak. Seemed to be lots of oil around the Shift Selector shaft. Called WH. We talked, and agreed it may be better to go to an Allison service shop. Nearest shop was in Virginia, north of Duluth. WH suggested I talk to Allison and I called their Tech Support (800 252 5283). Allison Tech support agree, go to Allison Service in Virginia MN. When I talk to the service tech he crawls underneath and comes back with Yup, seems like the Selector Shaft Seal. When the seal is removed we both agree there doesn't appear to be any problem with the seal but a new one is installed and we are soon underway. About 270 mile into our trip and I again find oil all over my Toad. By now I am no longer a happy camper. My clothes and hands are covered in black oil every time I unhook/hookup. Call Workhorse again. We discuss options and agree I can proceed to Stoney Creek ON.
Park it for the weekend. Talk to a mechanic I know, he says is the oil coming from the case vent? Oh Oh, why didn't I think of that? Crawl under, stretch my arm up and run my fingers around the vent. Lots of oil and dirt, Bingo!
Tuesday morning into the service bay at Detroit Diesel. Talk to the Tech. Tell him my probs and what has been done and what has been found. Yup, he says he will crawl under and check the vent. Back to me, yup oil from the vent. Asks me to open the back so he can get to the Dip Stick. He runs his fingers around the top of the tube and says there is a Vent Hole missing. Also says it is a common problem with Allison Transmissions. He drills the hole and I am out the door and on my way back to our campground. A few hours after we are settled in I call Workhorse and tell them what was found. Workhorse customer service claim to be taking notes. Thank me for the information.
Not long after, I receive a call from the Allison Service Shop in Virginia MN asking me if all is OK. I tell of my continuing problems. After that I call Allison Tech Support and ask if they are aware of the Dip Stick vent problem. Oh yes they say, we know all about it! All the OEMs were advised to vent the Dip Stick tube in 2 places. The OEMs are given a time limit to carry out the work, after that they are responsible for the cost. I call back to Virginia. Oh yes, we know about the vent problem!
By now I am back to my old "HATE WINNEBAGO" attitude.
Winnebago build the coach and should be aware of all recalls and engineering mods relating to the chassis they use. No one at Winnebago took the time to check engineering issues with the Workhorse chassis. No one at Workhorse bothered to follow through with engineering issues relating to the equipment used in the construction of the chassis. The selling dealer couldn't care less, they don't deal with chassis issues. I am out several days and many unpaid miles on my MH. No one pays me for my out of pocket expenses. As usual, the builders just shrug while the customer gets the shaft!
By the way, if you too own a new MH with the WH Gas Pusher arrangement you too may have the problem with a transmission oil leak. And OH YES, try putting oil into the filler tube! It takes a turkey baster with a thin hose attached to put oil into the transmission. And the best of luck to you too!

Beethovin · 08-25-2008, 01:05 PM

There are times when I really would like to reach out and touch someone at Winnebago, GRR!
We bought a new Adventurer LT on July 3, 08 with the new Workhorse UFO gas pusher chassis. Aside from the normal and frustrating minor problems at delivery we were on our way in short order. After one return trip to the dealer for some service problems we set off for Duluth MN. On our way I discovered a transmission oil leak (oil all over the front of our Toad). Called our dealer and found we had to contact Workhorse for chassis service. (I wonder how Winnebago handles Michigan Lemon Law issues?) Called Workhorse and was referred to a truck service facility in Superior WI. Talked to the technician who worked on the problem. He claimed the oil pan gasket was leaking. I am a retired mechanic so I had a look but didn't see anything. Anyway, no disputes, just replaced the seal and on our way. 177 miles later in St Cloud MN the same problem showed up (oil all over the front of our Toad). Crawled under and checked the leak. Seemed to be lots of oil around the Shift Selector shaft. Called WH. We talked, and agreed it may be better to go to an Allison service shop. Nearest shop was in Virginia, north of Duluth. WH suggested I talk to Allison and I called their Tech Support (800 252 5283). Allison Tech support agree, go to Allison Service in Virginia MN. When I talk to the service tech he crawls underneath and comes back with Yup, seems like the Selector Shaft Seal. When the seal is removed we both agree there doesn't appear to be any problem with the seal but a new one is installed and we are soon underway. About 270 mile into our trip and I again find oil all over my Toad. By now I am no longer a happy camper. My clothes and hands are covered in black oil every time I unhook/hookup. Call Workhorse again. We discuss options and agree I can proceed to Stoney Creek ON.
Park it for the weekend. Talk to a mechanic I know, he says is the oil coming from the case vent? Oh Oh, why didn't I think of that? Crawl under, stretch my arm up and run my fingers around the vent. Lots of oil and dirt, Bingo!
Tuesday morning into the service bay at Detroit Diesel. Talk to the Tech. Tell him my probs and what has been done and what has been found. Yup, he says he will crawl under and check the vent. Back to me, yup oil from the vent. Asks me to open the back so he can get to the Dip Stick. He runs his fingers around the top of the tube and says there is a Vent Hole missing. Also says it is a common problem with Allison Transmissions. He drills the hole and I am out the door and on my way back to our campground. A few hours after we are settled in I call Workhorse and tell them what was found. Workhorse customer service claim to be taking notes. Thank me for the information.
Not long after, I receive a call from the Allison Service Shop in Virginia MN asking me if all is OK. I tell of my continuing problems. After that I call Allison Tech Support and ask if they are aware of the Dip Stick vent problem. Oh yes they say, we know all about it! All the OEMs were advised to vent the Dip Stick tube in 2 places. The OEMs are given a time limit to carry out the work, after that they are responsible for the cost. I call back to Virginia. Oh yes, we know about the vent problem!
By now I am back to my old "HATE WINNEBAGO" attitude.
Winnebago build the coach and should be aware of all recalls and engineering mods relating to the chassis they use. No one at Winnebago took the time to check engineering issues with the Workhorse chassis. No one at Workhorse bothered to follow through with engineering issues relating to the equipment used in the construction of the chassis. The selling dealer couldn't care less, they don't deal with chassis issues. I am out several days and many unpaid miles on my MH. No one pays me for my out of pocket expenses. As usual, the builders just shrug while the customer gets the shaft!
By the way, if you too own a new MH with the WH Gas Pusher arrangement you too may have the problem with a transmission oil leak. And OH YES, try putting oil into the filler tube! It takes a turkey baster with a thin hose attached to put oil into the transmission. And the best of luck to you too!

UFO Pilot · 08-25-2008, 01:25 PM

I too had oil all over my Toad on the first trip. I guess I was lucky as I took it to the local Workhorse repair facility and they found the problem right away. On mine it was just a loose connection on one of the transmission cooler lines. Some teflon tape (I presume) and tighen the fitting. 8,000 miles later and not a single drop of trans fluid has been lost.

John_Canfield · 08-25-2008, 01:30 PM

Wow - how frustrating

- I can feel your pain!

Line most airline accidents, it was caused by a series of multiple events: Allison didn't vent the case, Workhorse either didn't get the word about an unvented case, or didn't follow through if they knew, Winnie either didn't get the word about an unvented case, or didn't follow through if they knew.

I had an issue of slow retracting jacks that took two years to finally resolve. Out of desperation, I took a trip to HWH for the issue and it took the tech about five minutes to tell me "oh yeah - we had a bad batch of jacks where the inner seal was compressed too much which caused slow retraction" ... what!?!? Why in the #$&$%@!* didn't you tell somebody (or maybe they didn't track parts) you had a bad batch of jacks??

Welcome to the club

Hopefully you are now done with major issues.

wagonmaster2 · 08-25-2008, 05:58 PM

John - HWH is good about that. We bought a new coach in Feb. 04, went to West Coast in May 04 and in June on that trip one morning the jacks wouldn't retract. After several phone calls to HWH finally just had to retract them manually by releasing the valves and proceeded on for several days until we could schedule an appointment with a Winny dealer. Took Tech 5 minutes to determine the control board was fried. When he called for replacement, HWH told him that was a new model control board and the were having problems with it. Said he was surprised it lasted us 4 months. Why in the h___ didn't they contact all customers with this information. It could have saved us 4 days vacation time plus the cost of extra nights stay and overnight express on the new part. Guess its always cheaper to let the consumer find their problems but maybe they won't complain about it.
Wagonmaster2
2004 Meridian 36G

steelheadbluesman · 08-25-2008, 06:05 PM

Beethovin - This stuff makes us nuts.... As far as you know is this vent-hole issue ONLY with the UFO gas pusher? Thanks for any info, 'cause I don't trust the companies to give it to me.

porscheracer · 08-25-2008, 07:16 PM

John . . . tell me more about the HWH slow jack issue. Our coaches are the same year and chassis - and my rears are getting slower . . . and slower . . . to retract.

Bob (WA0MQE) · 08-26-2008, 02:29 AM

Has anyone else had this vent problem? I did have a leaking seal on the shifter shaft about a year ago. But it was a very small leak. Not even enough to drip to the floor. Allison dealer replaced it and haven't had any problems since. I've not heard of the venting problem. Why would it only happen on some transmissions and not the others? There are a lot of Allison transmissions out there and this is the first I've heard of it.

porscheracer · 08-26-2008, 03:37 AM

Bob, I think it only applies to the new(ish) UFO chassis with the gas engine.

John_Canfield · 08-26-2008, 03:54 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by porscheracer:
John . . . tell me more about the HWH slow jack issue. Our coaches are the same year and chassis - and my rears are getting slower . . . and slower . . . to retract. </div></BLOCKQUOTE>Going OT here - apologies..

Norm - we had our slow jack retraction problem from the very beginning. In warm weather, they would retract within the specification time (but never quickly), in cool/cold weather they were out of retraction time spec. Two different sets of springs didn't cure the issue. One set of rebuilt jacks installed at HWH completely cured the problem and now our jacks are up in warm or cold weather within five minutes. In warm weather I have seen them retract in a minute.

It is possible you need new springs - yours could have lost their temper. If you are a DIY type, try a set of new springs. They aren't that difficult to replace and there are a couple of threads about how to replace them.
..OT end...

Beethovin · 08-26-2008, 06:38 AM

To the best of my knowledge, the oil leak issue is part of the Allison 2000/2100 series of transmissions. These are used in MH and commercial vehicles. The leak is not unique to the WH UFO chassis.

Beethovin · 08-26-2008, 06:44 AM

The rear HWH jacks on my Winnebago Adventurer LT are also slow to retract. I think it is simply due to friction. If they are very slow to retract I would suggest you check for pinched lines.

steelheadbluesman · 08-26-2008, 07:09 AM

Thanks for getting back on this -- So, if I want to see if this affects my rig, I feel around the fill tube for a small vent hole, right near the top? Any other helpful info on determining if there might be a problem? Thanks

porscheracer · 08-26-2008, 07:13 AM

Then I stand corrected. The only place I have heard of it was related to UFO's. I have a 3000, so I don't know.

Beethovin · 08-27-2008, 03:48 AM

With the dipstick in place feel just below the top (handle) of the stick. Hole is about 1/8" dia. With respect to what chassis is involved, for RVers the UFO uses the Allison 2100MH transmission. With respect to the venting problem, the 2000 series transmissions are configured in various ways for different applications. The Detroit Diesel technician who founnd my problem said that he has about 10 >12 transmissions on various commercial vehicles over the past year with the same problem. When I spoke to Allison Tech support, the response was 'OEMS' were advised of the problem and given a fixed time period to rectify the problem. After that leakage problems would be the responsibility of the OEM and not Allison.

From the OEM perspective, they buy the transmission from Allison and the Dipstick tube and stick from another supplier or make their own. The engineering info from Allison specifies fluid quantity and fluid height in the transmission. The OEM chooses / makes dipstick tubes / sticks to suit their particular application. On my WH UFO the dipstick protrudes above the rear mount radiator and Winnebago allowed no space at all for filling the transmission. From my perspective it takes a turkey baster with a tube attached to the end to put replacement oil into the transmission. Someone else can have the chore of trying to refill the transmission when it needs an oil change!

steelheadbluesman · 08-27-2008, 09:30 AM

Beethovin - Thanks for getting back! That answers my question. Best of luck with yours.

Ding-a-ling · 08-28-2008, 03:28 AM

Yesterday I had to have the "vent hole" issue taken care of by the local Allison repair center.

In June of '06 I had a minor leak and they replaced the selector shaft seal. Weeks later it was still oozing and they then said the shaft was machined slightly on the small side and replaced the shaft. All was well until this May after the local Workhorse shop changed the transmission fluid. It was wet in the same place, again.

Back to Allison. Maybe I have to talk to Winnebago because Allison said they cannot cover the labor $$ under warranty because the OEM should have done the vent hole modification.

But, why was it OK for two years? Is it really a matter of just how full the transmission really is? This isn't a new MH, I've got almost 49K miles on it.

Beethovin · 08-29-2008, 04:33 AM

After speaking to Allison Tech Support I realise that the company is not very forthcoming about the vent problem. I was a technician (of sorts) all my working life. The title changed as did the responsibilities over that period. Much of it was spent pushing builders to accept responsibility for design & engineering mistakes. In the case of the selector shaft seal on your transmission. The case vent is just above the selector shaft and oil venting from above runs down the side of the case onto the selector shaft. It is also blown rearwards (to the rear of the coach that is) by the air flow. Some of the oil migrates onto the sensor wire harness before flowing down onto the oil pan bolts. In my case it was not a large quantity of oil but it sure made a mess. With respect to the selector shaft seal, the type of seal used is known as a spring lip seal. It can accommodate some radial movement of the shaft without leaking. It can also withstand pressure buildup behind the seal up to defined limits. What the seal type can not withstand is dirt under the lip or surface roughness on the shaft. I won't try and second guess the techs who replaced shaft and seals. My own suspicion is oil venting from the case and running down over the shaft. The type of oil used in the transmission expands greatly as it heats up. If oil level in the case is at the upper fill point when heating begins and the ˜extra' vent holes are not in the dip stick tube then it appears that the oil expands up to the point where it is turned to froth by the gears and this froth then flows out of the case vent. On motorhome transmission series a ˜shallow' oil pan is used as opposed to a much deeper pan on some other applications. Perhaps Allison arranged the oil suction port and oil level requirements so that oil froth and temperature combine to create the vent problem. Unless Allison are willing to tell us we are unlikely to learn the reason for the case vent problem.

Ding-a-ling · 08-29-2008, 01:08 PM

Beethovin,

Very interesting.

This all started in Oct. '05 with the chassis CRANK fuse blowing intermittantly. In May of '06 Winnebago factory service and Workhorse found the problem to be "transmission fluid shorting out the Back up/Neutral switch." I never noticed a leak before that but afterward was advised by a technician I had a leak.

If I just now had to have the vent holes drilled, and at various times had the level of trans fluid adjusted, I'm having trouble believing I ever had a problem with the selector shaft or seal.

Beethovin · 08-30-2008, 05:05 AM

I would suggest you talk to Allison and lay out the sequence of problems. Ask them if they will fix/replace your transmission as a courtesy considering the length of time this has been going on.

It may be the torque convertor is generating excess heat and causing the transmission oil to expand more than is expected in the transmission design. Is your transmission oil showing signs of overheating, IE brownish color and burnt smell? Some chassis builders and some Allison transmissions have provision for transmission oil temp gauges even if the gauge itself is not fitted. Allison or a Detroit Diesel shop can tell you if your transmission has the wire harness and thermocouple fitted. It is only a diagnostic tool in most motorhome situations. The cure is something else as per the first paragraph.

Alternatively you could ask a Detroit Diesel service shop to replace the case vent with a vent hose and route the hose to a drip container that could be drained periodically. It would at least keep the mess in check. Not a cure just a way to keep the oil from messing things up.