Went thru the posts and could not find any that related to replacing a Allison 4000R Transmission.
Transmission cooler failed on our 2000 u320. Saw trans fluid floating on the coolant. The only way oil can get into the coolant is via the trans cooler as far as I know. The oil is not black so it is not engine oil. It is orangish beige oil. Coolant level seems to be little low too. Cannot check trans fluid level without running the engine and getting it up to temp. So have a trans cooler in route from FOT to a shop that will change it out tomorrow here in Richmond IN. Have to drive 6 miles to get there so when I do I can check the trans fluid level from the shift console that will verify that it is over-filled revealing the worse news I can think of right now. They will flush the coolant system and replace with new.
Allison says ANY coolant OR more that 0.2% water in the transmission requires a rebuild. So after I get the cooler replaced and the coolant cleaned up, will drive 105 miles to the allison dealer in Fort Wayne IN. They said if there is any contamination in the trans fluid don't even bother changing it when the cooler is repaired. The damage is already done as far as the trans is concerned. Don't waste $ on trans oil that will be drained again and scrapped in another 100+ miles.
Allison is talking $7K for a remanufactures trans, done by a company called weller. they are a certified allison remanufacturer and only use Allison Parts. Then there is the 2 days labor to remove and install. No telling how long we will have to wait to get the trans though. They have to build it up since it has a retarder on it.
Anyone have any other thoughts or alternatives. Full-timing is fun except when you breakdown. This will be only the second time in 14 years, but this one will be the most expensive one yet. At least we did not have the embarrassment of having it brought in on the HOOK.
Tom,
Go out and pull the transmission dip stick right now and let us know what you find. Do not start it.
A couple of members have had their cooler fail. Was about $11K with new cooler and rebuilt transmission installed. Do a search on the forum. Another had theirs rebuilt by Allison Mexico for $4xxx (they were in Mexico). Here is another possibility: HD4000 Rebuilt Allison Transmission, Global Industrial Automatics | eBay (http://www.ebay.com/itm/HD4000-Rebuilt-Allison-Transmission-Global-Industrial-Automatics-/182683754604?hash=item2a88cce06c:g:t~YAAMXQNo5TZCxj)
They have a contact number on the page. I think a heavier duty cooler is available.
Pierce
If you have a camera, a pic would be helpfull, as well.
Nothing to take PICs of yet. Waiting for rebuilt trans now. since it has a retarder, it had to be built to order. only takes 3-4 days to deliver. Took new FT cooler ($2250) to a local shop to have it replaced so we could drive 100 miles to Allison shop in Fort Wayne IN to have trans replaced. They said to be at their shop at 8AM. Was there and at 2:30pm they were going to put me in. I questioned that they couldn't do a good job in 2-1/2 hours. They agreed that if something went wrong I would be in their sop for another day and a night in a motel. NOT GOOD. I also realized that if they changed the cooler and cleaned up the coolant side and put the same contaminated Transynd back in No point to put in $400 of new fluid just to have it contaminate the cooler again and need to e replace a second time after the trans is replaced. Called Allison and they said there was no problem driving 100 miles to get it to them. They said they could change the cooler at the same time they did the trans. That way the cooler would be brand spanking new for the new charge of transynd.
So we added 2 quarters of std Trans fluid and hit the road. that is how much I had lost in this failure. No problems driving. Got to Allison they got us in within 1 hour and they checked the Trans fluid. It was about 750 PPM contaminated with glycol. Allison actually has a test kit that takes about 1/2 hour to run and it does a chemical analysis in a glass tube that gives you a range of contamination. Less than 50 PPM is still bad according to Allison.
We want to do another 180 mile drive to visit sites while we were waiting for the new trans. They said, no problem. The damage is done and it takes a lot of miles of contaminated fluid before the trans stops functioning. They said I could probably drive on it for another 2-3 months without a problem. Remember there is no alarm that says you have a failed trans cooler. Since the leaking is internal most people don't know they have a problem until they get an alarm from the trans that it has an error code OR is stops shifting all together. I was lucky that my wife pointed out a squeaking A/C belt and I notes a dark line in the Coolant burp bottle. Trans oil floating on top of the ccolant.
P.S. a trans cooler failure always has both trans fluid and coolant going both ways. Under way the trans fluid is higher pressure than the coolant and the trans fluid goes into the coolant. When the engine is stopped and cooling down now the Coolant pressure is high er than the trans fluid side so the coolant goes from into the trans side. My only concern is the possible damage of the trans fluid in the coolant getting into the radiator and engine. Allison said they have a machine that totally flushes the system with a neutralizing solution to clean it out. They must do a lot of these jobs to have special testers and flushing equipment for both the trans and the coolant systems. The Allison shop in Denver I talked to said they had 3 transmissions waiting to be rebuilt from the same cooler failure.
In heavy equipment engine oil cooler failures are common and there are degreasers that flush the oil out of the cooling system. The oil clings to the liners and the radiator tubes so a degreaser is necessary. I would think tranny fluid would clean easier.
Is there preventative maintenance that we can do to reduce this risk?
Can we gather information on the cooler failures in Fortravel coaches? It would be interesting to see how age effects these failures. How many have failed and what is the cost to replace before a failure?
Mark,
Oil sampling and coolant sampling for contamination but when you find out it is to late. Anti freeze attacks the bonding of the friction clutch plates disc to the backing plates, and it starts flaking off. If you do not catch it in time clogs the filter and transmission self destructs. . I am sure there is a air to oil cooler that would work but where would you mount? I like the idea of collecting information and see if there is a pattern on failures and change out before it fails.
Charlie
An air-to-oil cooler could work. I had one on my previous coach with 4060HD (Vogue) which was mounted separately just below the engine radiator. However, that coach had a Jake brake rather than retarder so the heat rejection needs were substantially lower than a tranny with a retarder.
Since I started reading here about these failures I've thought a bit about the issue and figured the best way might be a separate radiator with electric fan mounted alongside the A/C evaporator on drivers side with an upgraded alternator.
Big issue for me would be sizing. Unlike engines that are typically supplied to OEMs with heat rejection specs, I don't see any specs for that in Allison literature.
Another problem with air to transmission cooler is that in winter you can OVER-cool the fluid.
I have a Jake on my Cummins M11 and Allison.
Sounds like a better mouse trap is needed. The cost of a new/rebuilt trans because of a cooler failure seems like a very high price to pay for something that should be done another way.
I like John's idea of documenting this problem. If nothing else I would rather pull out the cooler and have it serviced or rebuilt at a certain age or mileage point.
Good point Brett. Guess the electric fan would have to have a thermostat control and maybe sizing for minimal heat dissipation without the fan.
It was never a problem for me with my previous coach as I've become very much a warm weather seeker. Once it gets down to 40 at night, I move further south ;D .
My OEM cooling system the transmission cooler and the engine radiator were combined, there was no standalone cooler for the transmission. I say were as a standalone cooler for the transmission was installed when I experienced a failure several years ago.
Roland
When I was a heavy equipment mechanic, coolant wasn't used. Just water with an anti-corrosion additive. The equipment didn't get acidity tests in those days. That was why the oil cooler failures. In my own Cat's I used a product called Stay-Clean which prevented bubbles on the liners and prevented corrosion. I never lost a oil cooler on my own equipment. Most of our coaches are well maintained and failure would be rare. The coolers always failed from the coolant side from electrolysis.
I think the coolers have to flow about 8 gallons per minute. The air cooler does sound like the way to go to insure there are no failures and a coolant/ATM mix. The problem with changing them out every few years is the Cummins/Allison cooler costs $2800. Detroits get off easy at $200 to $500 for a cooler that looks the same. Don't see any reason for the high price. The $2200 I saw quoted above is less than I have seen online. $11K is a high price to pay for a tiny leak in the cooler. That's as much as some coaches are worth.
For an air cooler with fan, the extra front to back wires could be used to turn it on.
Pierce
Try SEN-DURE MFG. STEWART WARNER COOLERS. But air coolers would be the way to go
U-tube bundle coolers can be bought with stainless tubes for slightly more than Cooper and a lot more erosion resistance. As small as it is I would guess under $1K. I will price up one in the next couple of days if I can find the pressure rating on the tranny side.
I believe with a retarder 60 GPM max flow
Charlie
Retarder Capacity
These coolers are really industrial commodity items. Size them by horsepower, inlet and outlet sizes, dimensions and there are likely hundreds of different stock coolers that would do the job.
Or just run water with dca4 additives per cummins. Not an option for all, of course but the antifreeze is for freezing temps.
Rocore Cooler Specs
On the first two attachments looks like I missed one side when scanning..... I can correct tonight and resend.
Sorry
They are available in stainless. That should end the erosion problem but they are not cheap at $2800. Here is the cooler with what should be the correct part number: Oil Cooler 29538013 for Allison Transmissions - Heavy Truck and Bus (24167AM)... (http://www.ebay.com/itm/Oil-Cooler-29538013-for-Allison-Transmissions-Heavy-Truck-and-Bus-24167AM-/262883899002?hash=item3d3519f67a:g:hSIAAOSwfVpYvdK1&vxp=mtr)
Pierce
It's interesting that if you read through some of this document you find that an oil-to-air cooler is NOT recommended for a tranny with retarder, although they do not say exactly why (heat rejection capacity?).
Two issues: Certainly heat rejection is one-- liquid (coolant) absorbs a LOT more BTU's than air in the same space/size.
The other is over-cooling in cold ambient temperatures. Would require a thermostatically controlled flow.
When I compare the $2800 + labor to the cost of transmission replacement, it seems like a plausible upgrade. I think of it in terms of risk-reward or return on investment. Similar to how I would approach a new roof for the house. Do I want to replace the roof with the "builder grade" materials originally used, or replace the particle board decking with plywood and the cheaper shingles with architectural grade shingles? It all depends on how long I plan to stay in the house.
We just started this coach experience and love it so far. But we're total newbies. I think we're in for the long haul but what if we decide in a year or two that a 34' is more our style than our 42'? Or, heaven forbid, that we don't like the coach lifestyle at all? I'm hesitant to over invest before we have more time under our belts. On the other hand, $2800 plus labor seems doable if we decide that both the lifestyle and this particular coach are our long term solution to wanderlust.
The other fun part about the stainless cooler is just the bragging rights around the campfire. ::)
The following pertains to a 99 320 40ft. SEN-DURE MFG, STEWART WARNER COOLER. 1 800 394 5112. PN 16311-1-5. Copper tube. List price 1325. IF order is 10 or more, price 1000. Other sizes are available. JC
If you look at the cooler in the link, it would probably cost another $3,000 to make something up to connect it to our lower radiator hose and the transmission and back to the engine. It may just be a tranny cooler for big rigs and nothing to do with our retarder. Doesn't look like it would have enough cooling.
Why try to re-engineer or over engineer the transmission cooler? The OEM ones work as they should, and last for at least 15 years.
Chris
No engineer here but a common sense type,have worked on generators offshore that run 24 hours a day and were built in the
early 80's,some of them have the original coolers.If the oil section never sees coolant and the coolant section never sees oil,what
will cause it to leak?
The only other thing I can think of is vibration,If I was in the mind set of replacing these items that may fail at some point I would
start replacing all the rubber mounts on the coach,I have'nt done any yet but it looks like many of the trans and engine mounts
could be done one at a time.
I still believe it is corrosion that kills them. Coolant can become acidic and if not changed will eat parts.
My point exactly,cheapest thing we can do is change fluids,way better to change sooner than later.The sampling helps but like
Brett mentioned,what if the sample is really bad,it was bad for some time period before taking the sample and was bad while
they process the sample.
Seems like good PM always -- pardon the pun -- boils down to fluids and filters.
This occurred to me too. If it lasts 15 years I'll be 80 and maybe ready to stop driving a 42' coach.
If your cooler is 12 or more years old and you plan to operate your coach another 3 or 5 years replacing it might be a good idea. We change things, fuel hoses, airbags, tires before they fail. Are we overlooking something here? When these fail it's expensive.
It's always hard for me to fix something that isn't broke even though I know it would be right thing to do. I guess you make a decision and live with it.
Most of the decision process depends on how much money we have,plain and simple.
Another reason to emphasize knowing the service history on a coach before purchase. Coolant maintenance should prevent all but a miniscule rate of failure.
Which is why we paid top CB for this one: "paperwork, paperwork, paperwork!" ^.^d
Local Allison dealer in Fort Wayne IN spent two days replacing the Trans cooler and installing a newly rebuilt (Weller) transmission. Finished the job Tuesday night on second shift. two days total in shop plus a ride test drive on the 3rd days morning before releasing the coach. Weller is an authorized Allison rebuilder. They are required to only use Allison parts in their rebuilds. Trans was pretty, painted red. Cooler was installed and the new trans put in.
Decided to take some recommendations to replace the hydraulic side of the cooler and Retarded Accumulator hoses with new ones. Reportedly some of these hoses can deteriorate on the inside and particle of rubber can get into the trans, particularly when the hoses are flexed during the cooler replacement. The three new hoses were $350 but I was able together them made while I waited at the hose shops.
Filled the trans with Transynd then they flushed out the coolant side with a chemical to dissolve the oil in the coolant. Removed the surge tank and burp bottler and cleaned they with high pressure jitney. Then they replaced the coolant with the newer ES Cummins Coolant and distilled water. (Had to go out and buy the distilled water. Tech said they only use tap water normally. He was impressed I insisted on distilled water.)
They reset the transmission using their computer. The reset puts the trans computer back to ground zero to relearn the trans shifting patterns with the new clutches. They told me they had one that they did not do the reset on and it quickly burned up after replacement. They inferred to me that whenever they do any trans maintenance, other than routine fluid and filter changes, they always reset it to protect themselves from having a premature failure.
Over all good job. Recommend the Clark Equipment Co in Fort Wayne IN
to do a trans replacement.
Where did you acquire the new oil cooler? Thanks jc
Is there not a coolant available that will meet the needs of a cooling an engine and not be so destructive to an Allison tranny? I understand that even a little bit of water contamination isn't good but if just water and it is caught soon enough, couldn't a complete overhaul be avoided? Maybe just a complete flush and refill? There must be some way to avoid such a catastrophe!
After all, these are garbage truck transmissions and are used all over the country, seeing much more wear and tear and less maintenance than our pampered Motorhome use.
Thanks for the write up. Glad you were able to get the work done so quickly. Appreciate the recommendation to replace the hoses -- seems wise. I'd also like to know where you sourced the new cooler.
Thanks!
Search transmission cooler to find where Sven bought his as he did his own.
Transmission cooler arrived (http://www.foreforums.com/index.php?topic=30722.msg267301#msg267301)
More or less than $11K for everything?
P
Got my cooler from FOT. They had it in stock and ready to ship that day. Yes it cost much more than you can get one from the manufacturer but someone posted that they had to wait 2 weeks to have it manufactured. Not sure the Manufacturer "Macore" had one on the shelf but I already had the FOT supplied one in route when I learned who the manufacturer was. FOT got it to me in 3 days ground shipping, 64#. Hoses were expensive, $350 dollars for the three of them. Total cost for the job, $14,500. Cooler, hoses, fluids, trans, and labor (16-17 hrs). I think they gave me a break on the labor since I was shagging parts for them while they were doing the work.
OH I forgot. when they removed the trans they found one of the drive shaft universal joints had a dried up cap and needed to be replaced, that was another $60 but the labor was the minimal since it had to be removed to change the trans. Interesting since I had the chassis lubed 2 months ago. Maybe they missed this joint or it had a fault that limited the grease getting to one of the caps.
P.S. From the Allison Service Tip " Trans... fluid containing greater than 0.2% water by volume contamination, regardless of whether it contains glycol or not, is considered contaminated and should not be used." Trans, with cooler, holds 9+ gals. 0.2% by volume is only 2.5 oz of water in 9 gal. Not as damaging as the glycol on clutches but still corrosive to internal past and reportedly can give bad readings on sensors used to control shifting. It can also rust and hit internal parts. Allison has a test kit for glycol in oil. there is also one available from Nelco Co. Saint Paul, MN, kit identified as "Gly-Tek". More info on testing trans fluid at "Automatic Transmission Fluid Technician's Guide (GN2055EN)". I think I was able to view and download this from the Allison website. It has much more info than anyone needs or can understand about the subject .
I am sure you can save $ on the job if you have more time to do it and can chose your own shop. Parts can be got for less if you shop and take chances they are the same quality. I was warned that there are shops out there that rebuild Allison trans with cheaper parts than the ones directly from Allison. But when you are full-timing and want to get a good job, warranted for 2 years, I chose to go to an Allison certified shop. And I was lucky to self diagnose the cooler failure, order the cooler immediately and get into a shop with in 3 days. They got the job done in 2+ days (to include a test drive) because they had a second shift that worked on it also