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McGruff38's avatar
McGruff38
Explorer
Nov 27, 2017

What is involved in adding a trans cooler?

I have a 1990 Fleetwood Flair 26 footer with a Ford 460 and 3 speed auto trans. The motorhome is rated at 3500lbs towing capacity, and I am right about there with my trailer and sandrail. My concern is my check engine light comes on periodically, and when Im climbing hills it stays on. Once im not climbing, it will turn off after 30 sec - 2min or so. Sometimes my engine temperature doesnt even have a chance to start climbing before it goes on, so Im assuming my transmission is getting hot. I dont have a temperature gauge for the trans, so im relying on the check engine light. So my question is, can I add a transmission cooler/gauge to this motorhome? if so, how much should I be expecting to pay for something like that?
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  • McGruff38's avatar
    McGruff38
    Explorer
    Nov 27, 2017

    Your check engine light is something engine, not trans related and a 1990 vintage would be a C6 and that would definitely benefit from at the minimum of a 6 pass cooler

    Sounds to me like low oil pressure, low oil level, clogged pickup strainer or a failing sender unit. Idiot lights work on the principle of continuity. I'd install an oil pressure gauge and a trans temp gauge if I owned the unit.

    You might try a heavier weight oil first.


    Hmm, maybe it is oil related. My factory oil pressure gauge usually reads about 3/4 of the way up when Im driving. While climbing hills, Im usually watching it like a hawk, and its usually pretty steady. The motor does burn oil, especially when climbing hills. If the oil level drops, the gauge will fall and the check engine light comes on. However, when the check engine light comes on while climbing, the oil pressure gauge was reading steady at 3/4. could the light be coming on because its burning oil due to the increased load?
  • gutfelt's avatar
    gutfelt
    Explorer
    Nov 27, 2017
    McGruff38 wrote:
    I have a 1990 Fleetwood Flair 26 footer with a Ford 460 and 3 speed auto trans. The motorhome is rated at 3500lbs towing capacity, and I am right about there with my trailer and sandrail. My concern is my check engine light comes on periodically, and when Im climbing hills it stays on. Once im not climbing, it will turn off after 30 sec - 2min or so. Sometimes my engine temperature doesnt even have a chance to start climbing before it goes on, so Im assuming my transmission is getting hot. I dont have a temperature gauge for the trans, so im relying on the check engine light. So my question is, can I add a transmission cooler/gauge to this motorhome? if so, how much should I be expecting to pay for something like that?


    sounds like a weak o2 sensor or even may be a emissions control mile service due lite;;regarding cooler easy to add on just make sure you put it between the rad out line and trans in line
  • old_guy's avatar
    old_guy
    Explorer
    Nov 27, 2017
    I would first take it in to have the codes read to see what is causing the light to come on, I've put them on pickups before, not that hard if you are mechanically inclined, just need to find a place to put it in front of radiator and then find out which one is the oil flow from tranny to large radiator and reroute it
  • Blutoyz's avatar
    Blutoyz
    Explorer
    Nov 27, 2017
    You probably have one but if not it is a very easy DIY add. Definitely not causing your check engine though but will not hurt to verify/add the trans cooler.
  • SidecarFlip's avatar
    SidecarFlip
    Explorer III
    Nov 27, 2017
    theoldwizard1 wrote:
    For that vintage Ford, the engine control computer does not know anything about what is going on inside the transmission.

    You may already have an auxiliary cooler installed. It would look like a small radiator and sit in from of the radiator and AC condenser.

    Adding a transmission temperature gauge is a good idea.


    +2.

    Your check engine light is something engine, not trans related and a 1990 vintage would be a C6 and that would definitely benefit from at the minimum of a 6 pass cooler

    Sounds to me like low oil pressure, low oil level, clogged pickup strainer or a failing sender unit. Idiot lights work on the principle of continuity. I'd install an oil pressure gauge and a trans temp gauge if I owned the unit.

    You might try a heavier weight oil first.
  • McGruff38's avatar
    McGruff38
    Explorer
    Nov 27, 2017
    Hmm. If the computer doesnt monitor the trans temp, then what else could be triggering the check engine light? Is there any way to tell after the fact?
  • theoldwizard1's avatar
    theoldwizard1
    Explorer II
    Nov 27, 2017
    For that vintage Ford, the engine control computer does not know anything about what is going on inside the transmission.

    You may already have an auxiliary cooler installed. It would look like a small radiator and sit in from of the radiator and AC condenser.

    Adding a transmission temperature gauge is a good idea.

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