zero Posted July 8, 2014 Share Posted July 8, 2014 Finally got around to installing a temperature gauge for the automatic trans. Been working fine but I'd like to know just how hot this thing gets on some long summer hill climbs. 145,000 miles on the trans and never been rebuilt yet. This on my 1988 Minicruiser. I did not want an electric gauge. Main reason being that if electric, the sending unit and wire hookups would be down low - up front near the road where they'll get wet a lot. Bound to corrode and give issues over time. I had a heck of time trying to get good info on the Net about direction of oil-flow from and to the trans. I wanted the gauge hooked at the outlet from the trans so I can get a reading of the hottest oil. I did not want to know the oil temp after it passes through the cooler/warmer in the radiator and additional air-cooler. I found a lot of contradictory info on the Net. even. Even found an old post where Derek was having the same info problem. I assume the same Derek as here? So I checked the old fashioned way. I unhooked the line coming from the trans to the cooler on the passenger side. Found out right away that is the oil-return line. So the hottest line is on the driver's side. Next problem was finding the right combo of fittings that the sensor bulb from the capilliary-Bowden tube would sit in the proper position. I.e. not blocking flow but still immersed in it. A standard Tee fitting would not work. Ends up a 1/2 X 1/2 X 1/4 reducing Tee worked perfect. Had to drill an 11/16" hole through the firewall for the tube and sensor to pass through. Got all done. Started the engine and had a substantial leak. It was from a pin hole in the OEM steel tube under a clamp that holds it to the engine near the oil-pan corner. Ends up the line had been vibrating inside that loose clamp for a long time. It was ready to go at any time and I just forced the issue a bit by working on there and attaching new hoses. Now I am very glad I did this work. If not for the gauge - for finding this steel line ready to spring a leak. Quote Link to comment Share on other sites More sharing options...
Derek up North Posted July 8, 2014 Share Posted July 8, 2014 If the info was correct, it must have been my post! Quote Link to comment Share on other sites More sharing options...
kgibson4 Posted July 8, 2014 Share Posted July 8, 2014 Once again, good work, JD! Nice write-up, too. Looking forward to the temperatures you record. The mechanical gauge that mine came with is hooked into a fitting that was brazed into the pan so I imagine the temperatures will be somewhat different than yours. Quote Link to comment Share on other sites More sharing options...
zero Posted July 8, 2014 Author Share Posted July 8, 2014 If the info was correct, it must have been my post! Actually you were a little ticked in the post because you stated you'd relied on info from the Net and found it to be wrong. You (if it WAS you) were installing a trans cooler on a Toyota RV. Quote Link to comment Share on other sites More sharing options...
Derek up North Posted July 8, 2014 Share Posted July 8, 2014 Show me the post and I'll tell you if it was me. Can't say I remember it though. "I still try to learn something new every day. The trouble is, I forget at least 2 things a day." Quote Link to comment Share on other sites More sharing options...
whyverne14 Posted July 10, 2014 Share Posted July 10, 2014 Speaking of which, I have a "Hot Tranny" light on my 86 Dolphin. But it never lights up. Which is good but how do I know it's working? Probably another big job huh? Sorry don't mean to hijack but it's another worry that just popped into my head. Quote Link to comment Share on other sites More sharing options...
zero Posted July 10, 2014 Author Share Posted July 10, 2014 Speaking of which, I have a "Hot Tranny" light on my 86 Dolphin. But it never lights up. Which is good but how do I know it's working? Probably another big job huh? Sorry don't mean to hijack but it's another worry that just popped into my head. Is it OEM or did someone add it? Must have a electric temp sensor somewhere in the trans-oil circuit. Probably the only way to know it works is with two tests. # One - remove the sensor - stick it in an oven set to 300 degrees F and see if the resistance changes. # Two -ground the wire going to the sensor and see if your light comes on. The temp-sensor for a Toyota RV is likely set to close and make the light go on at 248 degrees F (120 centigrade). That's pretty much standard on many OEM setups with transmission temp warning lights. Especially if a HD setup. 220F- 230 F is going to happen every time you climb a long steep hill. 240 and up you start getting into the zone with things are getting hazardous. A good transmission oil can offer good lube up to near 400 degrees F but at that kind of temp - rubber parts can start to degrade . And yes, I've seen the many charts showing trans-life versus oil-temps. Not sure how much I believe them as far as accuracy goes. Quote Link to comment Share on other sites More sharing options...
whyverne14 Posted July 11, 2014 Share Posted July 11, 2014 Thanks, jdemaris. The "Hi Trans Temp" light looks original, it's above the radio by the Overdrive light; which does work. Most dash "idiot lights" flash when you start the engine, so at least you know something is working. Not these ones. I'm adding this to my ever lengthening ToDo list. Quote Link to comment Share on other sites More sharing options...
zero Posted July 11, 2014 Author Share Posted July 11, 2014 Thanks, jdemaris. The "Hi Trans Temp" light looks original, it's above the radio by the Overdrive light; which does work. Most dash "idiot lights" flash when you start the engine, so at least you know something is working. Not these ones. I'm adding this to my ever lengthening ToDo list. Hey . . maybe my 1988 has the same light and I wasn't even aware of it? My OD light has two sides and two light bulbs. The one on the right is for OD "off." The one on the left lights up when the dash lights are on. Maybe hooked to a trans temp sensor too? I'd have to study the tech manual. I never had an owner's manual so was not aware of the "hot trans" function. NOTE - those little light bulbs are often burnt out. Both mine were bad when I got the RV. I went up and pulled the OD lights out of a scrapped 1988 I have -and that too had two burnt out bulbs. I findly got a pair out of another scrap truck. Those bulbs are not available at any auto parts stores I've tried. They are special proprietary bulbs and as far as I know, a Toyota dealer item only. My dealer wanted $15 each and I refused to pay it. If my used bulbs go out - I'll probably buy some $1 LED dash lights and put them in instead. Don't let some jerk at an auto parts store try to tell you those bulbs are generic and pull out of their bases. They do NOT. Bulb and base are soldered together. Note the two bulbs are different colors but the bulbs themselves are the same. They have little colored rubber covers pull off to change the colors. One blue and one sort of red or orange. Quote Link to comment Share on other sites More sharing options...
zero Posted July 11, 2014 Author Share Posted July 11, 2014 If you are talking about the same light I am (on the left of OD OFF) . . it's supposed to light up when you turn on the headlights/tail-lights/dash-lights. If it does not glow the bulb is burned out. Quote Link to comment Share on other sites More sharing options...
zero Posted July 11, 2014 Author Share Posted July 11, 2014 Thanks, jdemaris. The "Hi Trans Temp" light looks original, it's above the radio by the Overdrive light; which does work. Post the info if you figure out where that trans-temp sensor it. I have the factory repair manual for the truck-version of the A43D and it shows no temp sensor anywhere. If the RV has one -maybe Toyota built it into one of the lines? Or maybe the radiator? I've never noticed but guess I'll have to look more closely. I just noticed you're in the northeast. Toyota RVs are kind of rare around here. You are around 380 miles from my place in NY and maybe 200 miles from my old girlfriend (from 40 years ago) in PA. She has a Sunrader and I have a Minicruiser. So you are not alone in the rust-belt. Quote Link to comment Share on other sites More sharing options...
whyverne14 Posted July 11, 2014 Share Posted July 11, 2014 If you are talking about the same light I am (on the left of OD OFF) . . it's supposed to light up when you turn on the headlights/tail-lights/dash-lights. If it does not glow the bulb is burned out. I should have taken a picture. You're right. Two lights for the OD, one for OFF. To the left of that "Hi Trans Temp" lens. It says that right on it. And to the left of that, space for another but it's capped. I should check the "Hi Trans Temp" bulb first, I guess. Yeah, the Rust Belt. Which I worry about. This Dolphin spent most of it's life in Florida; so the underneath looks better than my 99 Buick, even though it's 13 years older. I got no place to put it except in the gravel driveway. I'm wondering if giving Zeibart some money might ease my mind a bit. I'd like to keep this Toy going for awhile. Quote Link to comment Share on other sites More sharing options...
zero Posted July 11, 2014 Author Share Posted July 11, 2014 I should have taken a picture. You're right. Two lights for the OD, one for OFF. To the left of that "Hi Trans Temp" lens. It says that right on it. And to the left of that, space for another but it's capped. I should check the "Hi Trans Temp" bulb first, I guess. Yeah, the Rust Belt. Which I worry about. This Dolphin spent most of it's life in Florida; so the underneath looks better than my 99 Buick, even though it's 13 years older. I got no place to put it except in the gravel driveway. I'm wondering if giving Zeibart some money might ease my mind a bit. I'd like to keep this Toy going for awhile. Some rigs from Florida rust something awful too. If near the coast - they can rot from the top down from salt air. Here in NY and in northern Michigan - they also salt the dirt roads all summer long that also helps destroy cars and truck. My road here in front of my house just got salted last week. I have no faith in treatments like Ziebart or the now-bankrupt Rusty Jones. Spraying used motor oil under a rig does a good job but not easy to do. Quote Link to comment Share on other sites More sharing options...
Derek up North Posted July 11, 2014 Share Posted July 11, 2014 Spraying with oil is a favorite in these parts. For what a gallon of cheap oil will cost, I'd prefer new over used. Used can have acids in it, I understand. One of the reasons to change the oil. 'Waxoyl' is a brand of rust inhibitor long used in the British sports car community. "Hardwax the chassis (www.waxoyl.com/en). Or brew your own with this recipe for home made "Waxoyl". It's an old fashioned rust treatment / undercoating:2 1/2 quarts turpentine12 oz. beeswax / candle wax1 quart light machine oilWith a cheese shredder, cut the wax into the turpentine, stir until the wax has dissolved, (takes a long time; you can use very low heat (a warm room) to aid but be careful) and thin with the machine oil to a brushable / sprayable consistency. Apply liberally. You can use a hand spray bottle to get into closed-off sections if you have a small access hole." I've seen variation on the theme using paint thinner. Once the turps/thinner evaporates, your left with a waxy oily coating. Quote Link to comment Share on other sites More sharing options...
Donnie Posted August 15, 2014 Share Posted August 15, 2014 Another variation on the theme is to use the wax rings that are used under a toilet bowl....Cheaper & just as good....We use this on our Land Rovers Waxoyl is priced too high..............just get a couple & add to your favorite carrier...........onward, Donnie Quote Link to comment Share on other sites More sharing options...
Derek up North Posted August 15, 2014 Share Posted August 15, 2014 There are lots of variation on the ingredients. I've seen paraffin wax and caster oil too. Quote Link to comment Share on other sites More sharing options...
Maineah Posted August 16, 2014 Share Posted August 16, 2014 Check out "Fluid Film" you can spray it with a Wagner electric paint sprayer. It is good stuff the frame is still black on my Tacoma after 4 years and I think ME is second behind NH in salt use! I use it on my farm stuff too. It is a non toxic lanolin based oil a gallon can should do the Toy home at least twice. Quote Link to comment Share on other sites More sharing options...
masinoshane Posted June 6, 2023 Share Posted June 6, 2023 On 7/11/2014 at 5:28 AM, zero said: If you are talking about the same light I am (on the left of OD OFF) . . it's supposed to light up when you turn on the headlights/tail-lights/dash-lights. If it does not glow the bulb is burned out. My gauge does not work and the lights are reverse somehow to when I turn my my dimmer knob up it lessens the light on the gauge and if I turn my dimmers knob down it gets brighter all the rest of my gauges get dimmer try to figure out how to hook this back up and figure out what's wrong with it any help would be appreciated Quote Link to comment Share on other sites More sharing options...
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