[Peter]

The transmission oil cooler can have two types of leaks. One is the coolant in the outer jacket can leak to the ground. That type of leak can be repaired by any competent welder as long as the steel outer jacket has not corroded away from rust and corrosion is why it is leaking. Depending on the location it can be welded in place once it is drained.

But if the leak is between the coolant chamber and the inner tubes or chamber containing transmission fluid it has to be replaced. Coolant in the transmission or transmission fluid in the radiator is a bad thing.

As to the cost, I would begin by searching the internet. Use words like intercooler, liquid to liquid intercooler and other key words that show up in a search. The key is to get one dimensionally similar to the existing one with fittings the same size. I believe the one on your coach is located to the left, down low when looking at your engine from the rear. It could be cylindrical or rectangular with the key needs being fitting sizes and location, exterior size capable of fitting, and internal volumes similar to what you have. If I were to manufacture that, even in relatively small quantities I cannot envision a price greater than a few hundred dollars so the price you were quoted is high. The labor to replace it, depending on issues with corrosion, shouldn’t be more than 3 or 4 hours which allows for cooling system draining.

[Peter]

If you don’t feel safe in purchasing this off the internet, I would contact Jeff Rowe at East Tennessee Luxury Coach. He will give you an Idea of cost and labor to replace.. 1-(423)884-6008

Steve

[Peter]

The links below were just from a quick search and show some ideas as an alternative to a $4000 cooler. I am sure some searching and a few phone calls will turn up a whole lot of other options.

http://www.makcotransmissionparts.com/TDC-19854.html

http://www.vanderhaags.com/detailview.php?part=24246996

http://www.mrcool.us/23525273-mtu-detroit-diesel-engine-oil-cooler.html

[glen]

I don’t want to alarm you, but its important to figure out where and how your cooler is leaking. As Jon said, if the leak allow engine coolant to mix with the transmission fluid, that poses as very dangerous situation to your transmission. I think Jon said that engine coolant and transmission fluid doesn’t mix well. I cannot emphasis this enough.

Before you move the coach, make sure you understand the impact to your transmission of this leak. Don’t be afraid to post more questions and information about your situation. We’re all here standing by to help you as best we can.

Don’t be afraid to reach out to Jeff Rowe at ETLC or the Large family at Expert Transmission. They both are PC advertisers and have a good reputation for helping Prevost owners out like you.

I’ve never priced heat exchangers/cooler for heavy equipment or over the road trucks, but I have looked at heat exchangers and coolers built for various motorsports applications and they seemed to be quite a bit less.

Good luck! Keep us posted.

[Archived]

Having just had an intercooler sudden and complete internal failure i can tell you howimprotantit is to get it checked before driving. My failure happened at 70 miles per hour 1500 miles away from home. I completely ruined the transmission requiring complete replacement. I looked at print out and was amazed that the coach was even drivalble for short distance after it happened. I had checked the transmission level the day before. I had even pulled dipstick to look at transmission fluid as i always do before a big trip (level checked with keypad). I was in Denver area and went to Stuart& Stevens in Denver. Great shop. Cost of intercooler part was well under $1,000. Cannot tell you cost of labor since was packaged with tranny.

The description of location is accurate, it sits low on left side of engine, and is a cylinder looking object.

[glen]

I would be more than happy to check that price for you. All we need is the cooler part number or the VIN of the coach. And when Jeff quotes you, you’ll know you are probably getting the best price possible.

[Robert]

Brian from American: How often do these things fail? Should they be replaced after a reasonable amount of time? Any hints of a failure? or is it a big surprise?

[Archived]

We replace up to 50 B-500 Transmission a year and they all come in under different amounts of mileage. As you know, your chance to keep your transmission alive increases as you perform a regular routine service schedule with a visual inspection for common leaks. But there are those times, where they will fail when they feel like failing.

Without knowing the true history of this trans, one can only make assumptions at what was done in the past. I will say there is a huge range of pricing when its comes to oil coolers. For our charter customers who requested a B-500 for their Vanhool, we offer them two options. A brand new oil cooler will run $2,2000, and a reman’d cooler will run $7000. And they can go up from there. So if the gentlmen who is asking about the cooler ever replies with a part or trans serial number, the price of $4,0000 could be “somewhat” accurate until then.

[AL]

Dick,

In my previous life we made fabricated steel products that were used as gravity separators. They obviously could not leak so we knew what it took to fabricate them in the tens of thousands.

The transmission fluid intercooler is nothing more than a steel outer jacket that goes over internal tubes or coils. Engine coolant enters and exits the outer jacket via threaded fittings and transmission fluid enters and exits the inner loops via threaded fittings also. If properly welded the fabrication should not leak internally mixing the two liquids. I suspect that event is very rare. Possible but not the typical cause for failure.

The outer jacket however will leak if corrosion occurs. Being low and almost out of sight we don’t get a good look at the intercooler so if it begins to rust, something typically found on the underside, it is only a question of time before it is perforated.

On my previous coach I noticed it had a lot of rust on the bottom of the intercooler so I cleaned the rust off, repainted it and from that point on inspected and repainted it as necessary to prevent corrosion and subsequent leakage. There is no doubt in my mind it is that type of thing that Jeff is including in his undercoach inspection because where located it is probable the drive and tag tires kick up stones and sand chipping the painted finish.

[Archived]

Good post Jon. As I was reading what you wrote about your previous coach, I got to thinking about Jeff Rowe’s thorough underside inspection of my coach when he does an oil change. Its like kind of attention to detail by Jeff that makes me wonder if an oil change at Jeff’s is in reality almost free.

[Rudy]

We can kid all we want about his price per gallon, but it his inspection that makes his oil change worth every cent. We have so much going on under our coaches that we often will not know of a potential problem until it occurs. I spend about 2 hours under my coach every 5000 miles looking, listening, and generally poking my nose in places I cannot see unless I am under the coach. The intercooler is only one example.

I think Peter does the same thing. He may not be able to get under his in his spare time when he is working, but I bet as soon as it is up in the air for service he is under it poking around looking for chafing, loose suspension or steering linkages, bad bushings, drying hoses, wets spots, air leak noises, etc. If whoever services the coach (I’m thinking Prevost for example) works from a list, it is probable they will only cover what is on the list. There is so much more that when checked might make the difference between a roadside repair, or a few minute fix with some new air hose.

We not only get peace of mind, we get a level of reliability that is very comforting.

[Greg]

I have seen transmission oil coolers fail in boats and cars (Ferrari 360/430). In those cases the leak is typically internal. The transmission fluid leaks into the coolant/raw water since it is under high pressure while operating. Once you shut the engine down, the process reverses and coolant leaks into the transmission oil since coolant remains under pressure for a while. The transmissions can be saved if caught early by flushing with fresh oil several times.

I think lack of coolant maintenance can be an issue causing corrosion in the cooler. Regular coolant changes and keeping up the additive package are important for the S60 cylinder liners anyway. Regular checks help too. If your transmission oil level suddenly is high or if the oil appears milky you probably have a coolant leak. Also, check the top of your coolant reservoir for oil scum.

Now excuse me while I check the transmission fluid and coolant reservoir….

Gerald

[Will]

Thank you all for the advise. Sorry I disappeared for a bit, work was crazy busy (probablly a good thing so I can pay for this – lol)

The shop informed me that it was the outer jacket only and there was no coolant in the transmission fluid – phew. Unfortunatley it can not be welded/soldiered due to the amount of rust/corrosion, so it looks like a replacement is in order.

Brian I will email you the Coach VIN. I do not have a part number – I will include all my contact info as well. We are currently in Massachusetts and it is at a FleetPride repair center.

Thanks again for all the great advise and quick replies it has been a great resource and keeps the local fleet mechanics here honest.

[Archived]

That was not unexpected unfortunately. It frustrates me to see examples of a few dollars saved in production, when that cost savings has a disproportionate impact on owners in the future. The push in fittings are probably the finest example, but each of us can probably point to a number of items whose failure exposes us to substantial costs that could have been avoided.

In the case of the intercooler a stainless steel outer jacket would not have helped Kim’s internal failure, but for everyone else who is facing problems relating to rust through on the transmission fluid intercooler it would have been a blessing. It is not unreasonable to expect an intercooler with a stainless steel outer jacket to cost to the manufacturer of coaches about $50 more than one all steel.

For preventive maintenance look hard at the intercooler, remove the rust and scale and put a good painted finish on it and inspect it closely every time the coach is in the air. If the coach is used up north this is especially important.

[Archived]

Yes, but did it rust from the outside due to external influences or corrode from the inside due to lack of coolant maintenance?