Leaking Transmission Fluid

[Fred Cook]

I am the new owner of this coach and I am trying to be patient but now.... I see a puddle under the coach that appears to be transmission fluid or possibly coolant.  I can see the origin and it is cylinder tube labeled SERCK Heat Transfer part number 3-1249T.  It is linked between the radiator and the the transmission so it must be the transmission oil cooler, right? It looks like it has rusted through on one end causing it to leak.  I have called several places including Fleetpride to find a part with no luck, and I fear this thing is going to cost a lot to replace.  Does anyone know where I can find a replacement part and what it would take to fix?

[David T. Richelderfer]

This may get you started.

http://beaveramb.org/forum/index.php/topic,6682.msg48277.html#msg48277

[Fred Cook]

This may get you started.

http://beaveramb.org/forum/index.php/topic,6682.msg48277.html#msg48277

Thanks David for the link. I called Rhonda and placed the order for PN 5-7063F, the newer oil cooler version. The price was $829 plus a $30 credit card fee. I offered to pay by debit card but the fee is the same. Shipping cost will also be added so we are looking at around $900.  It will take 3 to 5 weeks to have it delivered, which means we are grounded for a while.

[Keith Moffett]

Fred
Just a heads up.  If that is indeed the transmission cooler which it sounds like it is you might do a search on coolers on this forum.  From what you describe the engine coolant is leaking to the ground but if the ATF and the coolant get mixed even a little the result is awful.  Perhaps consider replacing the transmission cooler and the transmission fluid and filters as well.  At least have the fluid tested for engine coolant.
All the best and sorry for your coach troubles.

[Fred Cook]

Fred
Just a heads up.  If that is indeed the transmission cooler which it sounds like it is you might do a search on coolers on this forum.  From what you describe the engine coolant is leaking to the ground but if the ATF and the coolant get mixed even a little the result is awful.  Perhaps consider replacing the transmission cooler and the transmission fluid and filters as well.  At least have the fluid tested for engine coolant.
All the best and sorry for your coach troubles.

Ok.... now you have me worried.  From what I can see it is leaking out the aft end along the cap seal.  I checked it again a few hours later in that area and it looked dry again, like there is no leakage at all. Would that be an indication that it is actually coolant that is leaking?  On my recent 100 mile trip the transmission temperature stayed normal the entire way.  I did not noticed the leak until the next morning while it was parked in my driveway. Is there anyway of just looking at the transmission oil to know if it is contaminated? It would take at least a week for a turnaround analysis.

[Keith Moffett]

Fred
It is too easy to become overwhelmed when learning these systems.  There is just so much to learn and then a small problem begins to look huge.   Remember to stop and breathe.
A picture would help to make sure we are talking about the same thing.  Of the several types used, I am thinking your transmission cooler is seperate from the radiator.  It is a cylinder about 2 ft. Long with a radiator hose on each end and two
1 inch transmission connections on the sides.
Is this what you are looking at?  If it is leaking on the end are you sure it is rusted through or is it possibly a radiator hose connection?
If the liquid on the ground is red or green but watery it is coolant.  Red and thick and oily is transmission fluid.  Coolant leaking to the ground isnt too bad to fix .  My concern in the above post is the condition of the guts of the cooler itself if it is rusted through.  Seems logical to me though that if you were on a trip and it performed well, the oil test is more of a safety precaution.

[Fred Cook]

Keith,  first let me thank you for your patience and willingness to help me through this problem. The cylinder you described above is exactly what we are looking at. It is very rusted all over and the leak is obviously coming from the end of the cylinder weld, through the cylinder itself. I talked to Rocore today and they informed me that the newer version of the cooler will not be ready for another four months. But they do have the original version 3–1249T available now so I went ahead and ordered that. It ships tomorrow.  A Rocore tect talked to me for awhile and from what he indicated, the cylinder wall most likely rusted through causing the leak as you have also indicated. I also took a sample of my transmission fluid and sent it off this morning to Blackstone labs. Hope to get something back by late next week.

[Karl Welhart]

Fred,

You asked about if there was anyway to know if the transmission has been damaged from the coolant leak.  If you pull the transmission dipstick out and get as much fluid as you can on your fingers.  Look at the fluid very carefully to check the color. If it is a dark pink to light red, that is good.  If the color is very light pink or clear, that could be bad. Also, rub your fingers together and notice how the fluid feels. If it is gritty (like hand cleaner) or if you see fine particles, you may have a serious problem.

BTW, this device is a heat transfer unit.  It is using warm engine coolant to heat the transmission fluid that may not be able to warm up on its own.  The fluid analysis with show if there is a problem or not.

Good luck,

[Pat Long]

This thread got me to wondering so I took a look at my Transmission Cooler.  I am one of those guys that will do maintenance before it goes bad.  So I crawled under the coach and am still trying to hit the Knuckle Curve Ball heading my way.  My trans cooler is made by Serck Heat Exchangers and it to is a shell and tube design as is the others in question.  Don't have any idea where I would get a replacement cooler if I had to in a pinch.  Good to read all the provided information in this forum and will continue to do so.  I  will keep up my search and hope I am not hunting snipes. 

[Fred Cook]

This thread got me to wondering so I took a look at my Transmission Cooler.  I am one of those guys that will do maintenance before it goes bad.  So I crawled under the coach and am still trying to hit the Knuckle Curve Ball heading my way.  My trans cooler is made by Serck Heat Exchangers and it to is a shell and tube design as is the others in question.  Don't have any idea where I would get a replacement cooler if I had to in a pinch.  Good to read all the provided information in this forum and will continue to do so.  I  will keep up my search and hope I am not hunting snipes.

 I am receiving my replacement in a few days. The place I got it is Rocore Services and the number is (800) 645-2665 ext 1027 for Rhonda.  Pricey at $856 but at this point I have no choice other than just not go anywhere.

[Keith Moffett]

Fred
I seem to recall that in another thread on this topic an owner said they had replaced their cooler but one of the copper tubes inside had not been properly soldered which caused transmission damage.  Is it possible to have your supplier pressure test and certify the unit prior to you taking possession?  As always get it in writing. 

just my two cents

[Fred Cook]

Just got my lab report back from Blackstone Labs. The results show no coolant in the trans oil. Whew..... what a relief!  The lab did recommend that I change the oil soon. So, I have the new transmission oil cooler and transmission fluid bought already and I have an appointment Tuesday to have it all change out, including filters. Thanks everyone!