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-   -   AW4 whine (https://www.cherokeeforum.com/f2/aw4-whine-251424/)

dave1123 05-14-2019 09:14 PM

AW4 whine
 
Does anybody besides me have an AW4 who's pump whines after it gets hot? It only seems to whine when you start off from a stop after a period of constant low speed shifting, as in driving slowly delivering newspapers with many stops and starts, like 250 in 4 hours. The fluid is at the proper level and so clear it's hard to see it on the stick at night with a flashlight. The whine doesn't effect the shifting at all. Should I be worried about this or am I just being paranoid? I bought this used about a year ago so I think I'm going to change the fluid so I'm sure what's in it. Engine temp stays rock solid at 210* and I've never gotten a trans overtemp light.

Spencer_P 05-14-2019 09:34 PM

I don't have a whine but I do get bit of a rattle or clank when in drive that has made me paranoid the last couple times I've driven it :sweatdrop:

Cummins93 05-14-2019 09:43 PM

If the transmission outlet temps are kept down then I wouldn't worry at all. If you set up a gauge and you see 240+ sustained with a whine I would be concerned.

00t444e 05-14-2019 10:50 PM


Originally Posted by dave1123 (Post 3555868)
I've never gotten a trans overtemp light.

And you never will, because to my knowledge XJs don't have one.

Password12345678 05-15-2019 10:07 AM


Originally Posted by 00t444e (Post 3555881)
And you never will, because to my knowledge XJs don't have one.

Yeah, a trans overtemp light seems a bit too much of a luxury for an XJ haha.

downs 05-15-2019 01:55 PM

No trans overtemp light I've ever seen. Unless you put one in yourself. Older AW4s had a trans temp sensor port in the side of the casing (apparently only used in their toyota applications) that was capped off then later production years of the AW4 had that port deleted entirely.

One shortcut way to get an idea of what your trans temps are is to use an IR Temp gun on the transmission pan. It won't be a prefect reading but will get you in the ballpark. My trans pan IR gun readings are pretty close to what my gauge reads and my gauge sensor is installed in the trans temp port.

Do you have an external trans cooler installed? If not in your application delivering mail it would be at the top of my parts list of things to add.

The situation you describe leading up to your transmission whine is a perfect situation to develop very high transmission temps. Constant shifting at lower speeds with the torque converter unlocked plus constant stop and go of mail delivery is generating tremendous amounts of heat. And heat is the mortal enemy of automatic transmissions.

dave1123 05-15-2019 09:49 PM

Yes, delivering newspapers is very hard on vehicles. Brakes and tires catch hell and if your cooling system isn't up to par, can put tremendous strain the engine. I've never, up to this point, had transmission problems because I don't abuse them, making sure I come to a complete stop before shifting to the opposite direction. I can see where an aux trans cooler could be a benefit. Both my ZJ and my WJ had them, but the XJ doesn't. Good catch guy! Something else to do!

downs 05-15-2019 10:58 PM

I would put in a large trans cooler and at the same time put in a trans temp gauge. In your use you're going to be generating a lot of transmission heat and it's something I would want to keep a close eye on. Stopping before shifting doesn't really mean much temperature wise, at the speeds you're going the torque converter never locks up. The TC generates a ton of heat when it's not locked up, the constant shifting up and down through the gears will generate a bunch of heat too.

awg 05-16-2019 12:56 AM

thought I had a RPM related whine in 1st & 2nd...seemed to reduce a lot in 3rd & 4th

but there was an annoying power steering whine, making it hard to "diagnose"

as my vehicle with 210k+miles has an unknown service history, I replaced the power steering fluid with new Penrite
(that meets the FSM specs)

the power steer whine is virtually cured, and as it sounds like I no longer have a RPM-related whine in 1st & 2nd, I am hoping it was the PS pump

long winded way of saying change your PS fluid & ATF if overdue or cooked

I have a 12" X 8" cooler behind the grille, temps here get +100F

dave1123 05-16-2019 04:32 AM

Seeing as how my A/C compressor is missing and the entire system has been open to air for an unknown length of time, I'm not ever going to fix it. Do you think I can use the condenser as an oil cooler? I'm going to remove all the hoses and such anyhow, so I thought since it's already there, why not use it. Do you think it's too big and will overpower the radiator? IDK what the low side of the A/C is, but it should take the pressure. I've never seen more than 40 psi on Valvoline's T-Tech trans flush machine. The trans cooling lines come from the converter drain return and the other end is open flow to the pan.

I did just that on a Chevy truck that burst the trans cooler inside the radiator and it worked fine.


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