Not Good, not good at all: High Pitch Squeal

[$hifty]

So, whenever I drive over a highway summit (6%-7% grade), as usual, the ol' cruiser slows down to a fairly slow crawl--expected.

But, as it drops into say second or third gear, something bad happens. Lets say I'm in 3rd gear-as the RPMS start to climb, there is a very intense squealing sound coming from what has to be either the tranny or the driveline, but once it shifts into 4th and the RPMS drop, the squealing immediately stops.

The same goes for 2nd into 3rd.

Remember, this only happens up a fairly steep highway grade. My first inclination is to avoid the grades...fine. But, this grade just so happens to be just north of Boise and is pretty unavoidable if I want to go camping or hunting.

Any ideas?

Its a 90 FJ-62.

 

[Joe Egolf]

Have you checked universal joints??

 

[$hifty]

Have you checked universal joints??

Joe,

So far, I haven't checked anything. I'm really looking for the place to start.

When you say "checked" what precisely do you mean? Greased & Lubed?

 

[High Desert]

Even though it sounds like drive train noise..just for kicks, reach under the hood and check the tension of the belts....I'm just saying...

 

[Skniper]

Yup, thats what I was thinking.....loose belts or an idler pulley that gets unhappy under a load.

Would a broken motor mount create this situation under load??....just thinkin out loud.

 

[$hifty]

Good ideas fellas, but that is one thing that I have checked.

The noise, sometimes you can almost feel it, sound like it's right under the console and forward 24" or so.

 

[CaptHamster]

I'm having the exact same issue on mine...and I mean exact same. Steep grades, high revs in gear and under lots of load...I always assumed it was belts but I checked those and tightened them accordingly, and it didn't go away. Also, my squeal only lasts for a second or two, I've never continually run it at that engine speed long enough to see if it continues. As soon as I hear it, I back off a little.

 

[EUROTECH1986535]

sounds like the torque convertor is making the noise under load. once it goes into fourth the convertor clutch locks up stoping the sound. the clearances inside the tc have probally gotten a little to lose and is letting the turbine make contact with the stator. do not continue to drive this way as it will create metal and trash that will wreck the trannys cooling/lube system resulting in a bad melt down.

 

[CaptHamster]

Just following up on this in case anyone else needs it;

I replaced my alternator a couple months back and interestingly enough, even with the same belts, the noise hasn't come back. Could be loose belts or could be some pulley. Never know.

 

[toddslater]

The belts are sometimes tricky...especially the doubled up ones around the alt.

 

[Cruiserdrew]

Is your driver side motor mount healthy? (It will look normal even when bad)

Under high torque loads, if it's bad, the engine will lift and the fan will hit the edge of the shroud. That makes a shrieking noise you can often feel in the body of the car. Check the edges of your fan blade for abrasion from rubbing.

But belts do sound plausible

 

[haryv]

Sounds like it is time for the chassis ear

Amazon.com: Steelman (STE97202) Wireless Chassis Ear: Home Improvement