Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - TH-400 "whirring noise" at med. RPM's
View Single Post
  #3 (permalink)  
Old 04-12-2006, 11:24 PM
Crosley's Avatar
Crosley Crosley is offline
Hotrodders.com Moderator
 
Last wiki edit: T-350 rebuild tech
Last journal entry: Morris update 9-28-2014
Last photo:
Join Date: Nov 2002
Location: ... USA
Posts: 8,187
Wiki Edits: 1659

Thanks: 422
Thanked 108 Times in 104 Posts
Quote:
Originally Posted by NASCAR314
Stock 1973 Chevrolet Turbo 400 transmission in my Street Rod:

It has developed a noise present at acceleration from about 1,000 rpm's up to about 3,000 rpm's. Worse under load. Less in nuetral. Sounds like a "whirring" noise. Not a Grinding, scraping, or skreching noise.

It is not the water pump, alternator, belts, cooling fans, or timing chain (checked those). Seems to be originating from the bellhousing area, or flywheel area.

Trans. seems to operate just fine, shifts properly, pulls strong, ect..., Transmission fluid is full, and looks and smells like new.

Almost sounds like a "Blower Belt" on a Blown motor from inside the car. Or those "noisy" timing gears. It does change pitch with increase in RPM's

This noise seems worse during colder weather, and then dissapates somewhat as engine / trans. warms up.

Any idea's? could it be the transmission fluid pump? torque convertor?


sounds like the pump is working hard to pull fluid in.

I'd drop the pan and change the filter if that has not been done for a while


__________________
Some people are like Slinkies... Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.