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700R4 making noises

Hey guys, i have a 700R4 in my 79 GMC Sierra. Ever since i had it installed, it makes a humming/howling sound...especially when i accelerate or when it goes into overdrive. And if it's really windy or i'm climbing a hill, the humming/howling gets really loud. I've dealt with this for awhile now.

But now, another noise has appeared...a knocking/rattling sound when i accelerate fast or when it goes into overdrive. When i let off the gas, or once i'm cruising in overdrive, the knocking/rattling goes away...but comes back as soon as i give it gas. Also, if it's really windy or i'm climbing a hill, the knocking/rattling stays there and is kinda loud along with the humming.

I should also point out that the other day i found tranny fluid all over the top of the air cleaner lid. It hasn't happened since though, and i've driven it a lot.

I know i gotta get the guy who installed the 700R4 to look at it, but i'd like to see if anyone here has come across this kind of problem and knows what it is and what can be done. Any help or info would be greatly appreciated. Thanks.

Re: 700R4 making noises

I would drop the pan, and inspect the fluid and residue in the pan, and look at the magnet if there, if no magnet is there i would get one and run it through the fluid, almost sounds like the pump, or one of the roller clutches,

Re: 700R4 making noises

Sounds like the pump is whining and the converter has loos crap in it. If it was rebuilt take it in on warranty and get it fixed for sure
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Re: 700R4 making noises

Also, make sure the vent tube has no restrictions. Fluid on the air cleaner could only come from the dipstick tube and would be caused by excessive pressure and nowhere for it to go

Re: 700R4 making noises

Thanks guys, i appreciate it....i'm gonna look into all these suggestions. And if anyone else has some ideas or thoughts, let me know.

Re: 700R4 making noises

Make sure it's not low on fluid. Sometimes you can hear the pressure regulator valve in the pump whine if it's low on fluid.