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Overheating concerns for 8V92 - need advice
#21

I honestly don't recall seeing a smaller tranny cooler. The guy who picked it up said it appeared to be an Allison to him. My garage in Sioux Falls recalled it being a Cummings. So now if faced with the choice of the two do you have a recommendation? If there is no cooler at all should I ask for one to be installed?

The hills I climbed were not that big. It's I90 between Billings and Bozeman. I saw one 6 percent grade but went down that one. I managed the engine temp to no more than 200 concentrating on the RPM being close or at 2000 as instructed and trying to keep the turbo boost from maxing. When this did not work I slowed and geared down. The engine temps stayed in a static range but the transmission shot up before I knew it (too focused on other gauges) and frankly was not sure what was too hot for that since that gauge was not marked with a red mark nor did I ever ask anyone about it. There was lots of bridge construction and in third gear going 45-50 I was a steady 2000 rpm which was the target climbing hills from the posts.

There should be a driving school for these old 2 strokes. This coach will be brand new now. All new interior, rebuilt engine, new tranny, all new water bay, all new lighting...and on an on. It was and probably will still be passion again, but right now we are exhausted. Going to Yellowstone today. Found a room at the Kelley In in West Yellowstone (literally the only one left after calling 6 others). Taking the kids fly fishing tomorrow and will try to focus on the kids. My youngest is a worrier and got very anxious about this all so we will work on his to do list for this vacation.

Thanks for any advice. Mechanic is calling me this morning at some point.

Todd & Dawn Flickema
Former owners of a Classic 1984 Newell
71 Karmann Ghia
Sioux Falls, South Dakota
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#22

Your coach was almost certainly built with an Allison transmission. If it is a four speed, the HT740 although there is a small chance it had the Allison 5 speed MT653. The MT653 was not as strong a transmission and I don't think it was used in very many, if any, Newells with the Detroit 8V92 although it was used with the lower horsepower Detroit 6V92's and Cummins 903's.

It doesn't sound like you did anything wrong in your driving technique that would have caused the transmission to fail. From what you have written, you handled the situation exactly as you should have. 2000 rpm's will not hurt a transmission that is not on the verge of failure anyway.

Don't try to second guess yourself. Things wear out and when they do, try not to blame yourself. Enjoy your vacation with your family. Kids sense when their parents are worried. Be happy and the family will be happy.

Michael Day
1992 Newell 43.5' #281
NewellOwner.com
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#23

Richard mentioned checking for water in the transmission. Assuming there is no water found in the oil, transmission temperature should not be a problem. While I have a different engine and most likely a different model transmission, my experience may be informative. It seems to me that the only reason for keeping the engine RPMs high going down a steep grade is to maximize the effect of the jake brake. Since a diesel has no vacuum, down shifting going down hill has no braking effect, but the higher RPMs helps the jake do its job. The transmission will normally heat up going up a grade, and will heat up some more going down grade because of the jake. This last month while traveling from California on I-80 to Wisconsin, I went up and down several mountains that were up to 40 miles up and down. I use synthetic oil in my unit and the transmission temperature, while normally 200 degrees, went up to as high as 254 degrees on two of these long mountain stretches. As far as I can tell, there has been no damage to my transmission and it has operated normally during the remainder of my trip. Sorry for such a long post, but it seems to me that whatever caused the transmission to fail, heat or RPMs should not have caused it to crater. Allison has told me to not worry about heat as long as it has synthetic oil. Other may have a different experience.

2001 Newell #579
tow a Honda Odyssey
fun car: 1935 Mercedes 500K replica
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#24

Todd, when you had the engine rebuilt did the shop check out the condition of your transmission while it was out?  I'm pretty sure you have an oil and transmission cooler built into the radiator just like I do, and I'm pretty sure the tranny is an Allison.  It's a good idea to have the transmission fluid checked once a year and the filter changed.  A periodic check of the condition of the fluid will help avoid catastrophic failure.  Frankly, like Michael and others said.....don't blame yourself....it doesn't seem like you did anything wrong.  I routinely keep my RPM's at 2,000 on long climbs, or while in traffic to keep that fan spinning at maximum velocity to keep air flowing across the radiator fins.  Once the transmission heats up it takes much longer for it to cool down than the oil and coolant....at least that has been my experience.....on the other hand the Allison transmission can operate without harm at much higher temps than the 2 stroke.


Clarke and Elaine Hockwald
1982 Newell Classic, 36', 6V92 TA
2001 VW Beetle Turbo
Cannondale Tandem
Cannondale Bad Boy
Haibike SDURO MTB
http://whatsnewell.blogspot.com
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#25

I recall asking if the transmission was ok and they said yes. I take it in for annual service and they check everything is my assumption. 

Todd & Dawn Flickema
Former owners of a Classic 1984 Newell
71 Karmann Ghia
Sioux Falls, South Dakota
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#26

Todd, I have the transmission out of my 86 sitting in my garage in Boise Idaho that I will donate for the cause. It was shifting fine, it's out because the engine overheated and seized. I sent you a PM with my phone number if you're interested.

Jon & Chris Everton
1986 40' Dog House #86
450 hp ISM 5 spd ZF Ecomat 2
2004 Range Rover L322 Toad
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#27

Jon, it is incredibly generous of you to help todd out by giving him your transmission. I just talked to him and he is so grateful.

by the powers vested in me as the guy who controls the titles of the gurus.

I Title you Guru Samaritanus

which will be your Title on the forum under your username.

Thank you again,

Tom

2002 45'8" Newell Coach 608  Series 60 DDEC4/Allison World 6 Speed HD4000MH

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#28

Amen Tom. I told Tom that Jon is officially St. Jon in our house. The poor guy thought he could rest after a long night of working last night until I called. I also got a help from the shipping company that discounted their rate by 75% after asking me why we are shipping a transmission. Traci at Redday is also someone we are in debt to for that kind act. 

I asked the head guy at the shop what happened. He said the clutch plates were bad and it over heated. He said it was a tired old transmission. It will arrive at their shop Thursday and will be installed (I hope) and ready by Friday so that we can stay on schedule with coming home. We will drive the jeep and coach to Billings separate to make sure everything is ok before we try towing again. 

Todd & Dawn Flickema
Former owners of a Classic 1984 Newell
71 Karmann Ghia
Sioux Falls, South Dakota
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#29

Wow Jon.....wow! You are numero uno in my book! Todd....this is what owning a Newell and being a Guru is all about ! FRIENDS HELPING FRIENDS! !


Clarke and Elaine Hockwald
1982 Newell Classic, 36', 6V92 TA
2001 VW Beetle Turbo
Cannondale Tandem
Cannondale Bad Boy
Haibike SDURO MTB
http://whatsnewell.blogspot.com
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#30

Have the old fluid tested for water content and ethylene glycol !!!!!! Water in the ATF causes the clutch plates to break down. It shouldn't cost more than 25 bucks for the fluid analysis.

As Clarke said the tranny cooler is INSIDE the radiator. It's cheap insurance to make sure you don't fry the next tranny.

Thanks Jon, that was a gracious move.

Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home Cool )
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