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D5N tranny overheating

guisep3 ยท 2020-07-28 00:00

OK fellas, we have been using the D5N to install backfill for about 3 weeks..it's a.slow process. Ambient Temps around 90 deg plus. Oil temp light comes in around mid day. If Operator slows down the temp will come down quickly. What's a few good easy diagnositics before I get into serious money getting a cat tech involved? Does this machine run the tranny oil thru a cooler? If so I'll certainly power wash the rad and cooler first. Then I'd assume there's changing the transmission filter? Any exact location of said filter? Operator did find that the tranny was about 7 Gallons low about 2 weeks ago. Alarming considering cat changed 5 hoses for me 6 months ago? Figured they would have checked all fluids after losing fluid due to hose change. Thanks for any input.

Replies25
  1. #1Nige2020-07-28 03:05

    A lot of the questions you ask could be answered if you had an Operation & Maintenance Manual, a $50 download from Cat. Post a Serial Number and I can walk you through the process. How is he checking the oil level.? Engine stopped or engine running..?

  2. #2Welder Dave2020-07-28 03:22

    The oil temp. light is for the transmission? I thought I read on the forum awhile ago about another Cat machine that would overheat the tranny oil if it was over filled.

  3. #3guisep32020-07-28 07:34

    Engine running. As per the instructions on the tranny dip stick. He's a veteran guy in his late 60s..

  4. #4Nige2020-07-28 13:07

    Gotcha, but I had to ask........

  5. #5guisep32020-07-28 16:23

    We powerwashed the radiator and cooler. They were packed solid with dirt. Nige My question is is there an accessible filter for the tranny? And do you think it's a pressure issue with poor circulation of the oil? I know transmission oil cap is 32.3 gallon. Bad flow would certainly heat up the oil in sure.

  6. #6Nige2020-07-29 04:01

    You don't give a Serial Number so it's a little bit of a shot in the dark ..... BTW all the illustrations below are taken from the $50 manual I referred to above. The tractor probably burns more than that value in diesel every day. Transmission filter can be one of two types. Whichever type it is located behind the access cover on the rear of the machine. If you replace the filter I suggest that you cut open the old one and look for debris in it. There are plenty of "how to" videos on YouTube. I'm willing to bet that if Cat topped off the oil when the hoses were replaced that they neither changed the filter or removed & cleaned the magnetic screen in the transmission suction line. To get at that screen will require the transmission oil to be drained and a section of the belly guard removed. Can I ask where you got that number from..? Because when I look at the O&M Manual (back to that pesky manual thing again) for a D5N it quotes 27.7 gallons for the transmission oil capacity, so it appears as though you are working with incorrect information.

  7. #7guisep32020-07-29 08:08

    Nige Here's the serial number D5N XL AGG02056 I will admit I Googled the tranny capacity. I can't recall exactly the form I found it in on. I'm definitely open to being wrong! Appreciate your time Nige. Additionally I do have a operating manual. I have in my truck now and will certainly take a look at the illustrations you posted.

  8. #8Nige2020-07-29 08:35

    Also be very aware of the word "Approximate" in the title of the "Refill Capacities" section, because that's what the numbers are - approximate. The table below is taken from the O&M Manual for AGG02056. Every component/system should always be filled using a dipstick, level plug, sight glass,or any other method to ensure the correct oil level rather than simply dump a certain quantity of oil into it.

  9. #9guisep32020-08-30 22:38

    Nige I dropped belly pan and and found some serious problems. I had a tranny leak. I spent 8 hours cleaning mud 3 inches thick soaked with tranny oil. The 2 main hoses that come from the pump I believe part numbers 239-0931 and 239-0932 were completely destroyed. They were swolen and when you touch the hose it oozed oil out. Now that was an easy fix. My real problem is found an unbelievable amount of wires that were bare. I believe it's due to the caustic nature of the tranny oil and the wire insulation. I did a very thorough cleaning and discovered many more wires in the main harness exposed and when I went to repair the insulation more came off. The main connector in the back that connects to the tranny with a 16 on connector was dirty. When cleaned up, I noticed a bundle of wires that were bare. We used liquid electrical tape and it seems to have helped tremendously, however it's not a permanent solution. Do you have any idea how much a new harness would cost for the part, and how much for the labor? I called my local Cat dealer and they are telling me $2500 for the harness and $7500 to do the repair. I'm shocked and a bit queezy by it. Does this seems reasonable or is this too much? Any input would be greatly appreciated. I know youre a cat guru. I posted a pic of the harness from my parts book.

  10. #10Nige2020-08-31 05:18

    What Part Number harness are you planning on replacing.?

  11. #11guisep32020-08-31 07:25

    Nige here's the part number. 237-4485

  12. #12Nige2020-08-31 08:36

    I seem to recall that there was an issue with wiring harnesses some time back where a vegetable-based material was used for the insulation. Over time it hardened, cracked, and fell apart just like you are describing. See this thread. i'm not 100% sure it's the same problem but it sure sounds like it - HeavyEquipmentForums 237-4485 is the complete Platform Wiring Gp. In that group item 17 is the wiring harness P/N 275-8262. Price for the harness as far as I show it is around $2575. Replacing the harness will be time-consuming but not too difficult. Could you do it yourself..?

  13. #13guisep32020-08-31 08:56

    Nige Wow I'm shocked about the vegetable based insulation. The pictures shown are exactly the same situation im in right now! Any chance there was a recall on this? As far as doing myself....I could do the work but my concern is do I need to remove the erops? Once I remove the harness the machine is most certainly a statue. Removal of the erops itself seems like a big job start to finish. Another question I have for you Nige, is there a safe compatible oil I can use to flush and replace the transmission oil? I know cat has spec oil for everything. I think my operator added aw46 to the tranny when he found it to be approx 7 gallon low. Hence the major leak we had that saturated the entire underbelly.

  14. #14Nige2020-08-31 09:10

    I suspect this may be a similar issue. Your D5N was manufactured in 2005, right where the affected excavators were built. Even if there was a recall it would probably have expired long ago and it would need dealer-level access to SIS to find it. Never done one myself, but I wouldn't have thought it needed the ROPS removed. As an absolute minimum a lot of panelwork will have to come off, that's for sure. Hopefully someone else can chime in here. So much for being an "veteran guy" as per your post above ........... The transmission oil should be an SAE30 weight oil that meets Caterpillar TO-4 specification. All major oil manufacturers make a TO-4.

  15. #15guisep32020-08-31 09:20

    Yes I agree...vertern guy that does stupid **** like that! I'll call my local supplier for oil.

  16. #16.RC.2020-08-31 16:54

    Should ask for the price on the one that uses copper wire, not gold.

  17. #17Nige2020-08-31 17:57

    It's the main machine harness, a ***koff great big long thing with branches everywhere.

  18. #18.RC.2020-09-01 03:20

    Probably is, but come on $2500. Even if there is $300 of materials in it, does it take one person on $30 an hour 73 hours to make it? Yes I know there is design work and storage costs to allocate but I still think that price is a "Jesus sex with titties Christ" moment.

  19. #19Cmark2020-09-01 03:33

    sounds like you found yourself a lucrative business opening

  20. #20.RC.2020-09-01 05:08

    That is not a valid argument. The cost to reverse engineer then make up a harness is not going to be cheap given so few are going to be sold. If you were going to make up 15 000 or more as Cat would have done, the development and assembly line costs would be absorbed over that number. Of course without that harness the dozer is nothing more then a garden ornament.

  21. #21Nige2020-09-01 11:08

    Just looking at the major connectors in that harness there are (at Parts Dept prices) $1000-worth of Deustch connectors in it for a kickoff. That $1000 does not include all the wire & terminals. The harness comprises 81 line items. See attached. If you could make it for $300 in parts + labor you've found yourself a calling.

  22. #22.RC.2020-09-01 18:27

    But if it was made out of very expensive components, it would not be falling apart in fifteen years requiring replacement.

  23. #23Nige2020-09-01 19:40

    A wiring harness is a replaceable item. We completely re-harness our machines every time they are rebuilt, anything from 15-18k hours. Cost varies but I would guess a dozer probably $5-10k, but that would be less than 5% of the component cost for the rebuild. The state of some of the harnesses when removed makes you shake your head and wonder how they ever worked.

  24. #24guisep32020-09-01 23:17

    The shame of it is the dozer only had 3850 hours. It's in great shape. Really was praying for a miracle of a possible recall..as another has said, I gotta pay the piper or I have a 30000lb lawn ornament!

  25. #25.RC.2020-09-01 23:32

    You should look in the bright side, I looked up the price here. It is around US$300 more expensive in this country.