whining noise in TH400 at low rpms

[Harbone]

I have a supposedly well built (900 HP capabilities) TH400 that has a sllight whine at lower RPMs, 1800-2300, doesnt make noise at any other RPM, cars has a 3200 stall. mostly noisey at those rpms in 1st and second and just slightly in 3rd then goes away. no metal in the pan, fluid is spotless and not burnt. It also has a trans brake,reverse manual valve body and 3200 nitrous converter, trans has high perf clutches and bands,h/p heat treated sprags,increased line pressure, pressure tested case and deep pan. it doesnt act like it has anyproblems, shifts firma nd is not slipping. car has aluminum floorboards so i am sure that just makes it louder on the interior.

Is this a "normal" noise for a "overkill" tranny

[TopspeedLowet]

Chris, your pick up may be sucking air at the case where we use two O rings to seal it. I have run into that before. The other cause could be a restrictive cotton type filter. I use a filter for a 540 Allison trans that would come in a blue bird bus, this uses a screen for a filter medium. Part # FK 135 in the ATC brand. You will need a 400 pan gasket purchased separate. The filter is the exact same as a 400 configuration, but preferred for racing and high oil flow!
Bruce

[Harbone]

bruce,
thanks for the input!!!!

[DRTRCR22]

Hey Chris... are you sure it is not just trying to talk to you...?
Something like "Come-on big boy... is that all you got? Come-on you can do better than that, stick your foot in it and lets going hunting...!" :lol:

Just kidding... but ya never know...? :P

Jim

[Harbone]

Hey Chris... are you sure it is not just trying to talk to you...?
Something like "Come-on big boy... is that all you got? Come-on you can do better than that, stick your foot in it and lets going hunting...!" :lol:

Just kidding... but ya never know...? :P

Jim

Jim,
Well maybe, it doesnt make the noise when I mash the throttle! I just have never had a car with a tranny that "built" in it before and didnt know if it was a normal noise or not

[zipper06]

Hey Chris,
It may be irrevent, but the 4L80 in my duelly starting whinning in low gear about 5 yrs ago. The guy that builds my PG's told me it was the plantatries, he also said don't worry about it drive it until broke, because the rebuild would cost about $1600.00. I have done just that, pulling the inclosed trailer, open trailer, etc. and have put 40,000/50,000 miles on it since it started whinning, and it still works as good as ever.

Zip.

[cepx111]

I had a C4 that did the same thing.

I was told it was the planetaries thrust washers and not to worry about it, I didnt.
Sold the car 4 years later, tranny was still working fine.

[Tod74]

I had one that whined and it was the pump. Only heard it at slow speeds.

[kbartley]

my 400 started doing this at slow speeds mostly when just starting to move until it goes into 2nd. I was told there could be moisture absorbed into the fluid. I hust haven't changed it to see. I have it in my old 2wheeldrive suburban 454eng. I use to tow the FED with. I'm hoping that's what it is anyways. Hope it's not the pump or something to involved. I had that tranny gone thru 3trs, ago and have changed the fluid/filter once since then.
Kris

[MEMRACING62]

I had one that whined and it was the pump. Only heard it at slow speeds. X2 had the same problem , pump buzz,

[blwilliams]

Like already mentioned, pump, planets.
Really any thing with straight cut gears will have a tendency to whine if no lube or too much clearance/backlash.