Hey guys, I got a 1990 f250 with the e40d transmission. Experiencing a noise I can best describe as scraping or rattling but what has me confused is the how and when it happens. I start the truck and run it there is no noise at all until after about 5 to 10 min of driving. Only happens over 35mph and usually only in 3rd (it's worse in 3rd) or 4th after the RPMs drop down a little which I guess is the TC unlocking? When the trans is cold it seems to shift extra crisp and RPMs stay steady through each gear. Once it warms up and the RPMs drop after 3rd and 4th gear shift is when I hear it. My knowledge of transmissions is limited and knowledge of automatics is even worse so forgive me if I sound stupid. The noise gets worse if I'm light on the throttle and goes away completely if I step on it. It gets louder as rpms increase sounds like something is spinning around in there. Fluid looks decent and is full on the dipstick. Is my TC on it's way out? Seeing what y'all think before I take it to a trans shop and have them try sell me a new one haha.
E40d noise
- Thread starter jbart90
- Start date
Only reason I didnt think it was the driveshaft is because it doesnt happen all the time. Figured that if it were the driveshaft I'd hear the noise all the time.
*edit* Actually now that I think about it the truck has a 1pc driveshaft
*edit* Actually now that I think about it the truck has a 1pc driveshaft
MtnHaul
Full Access Member
If you have a transfer case there is a known issue with vibrations manifesting as a very noticeable rattle. Mine rattles once I hit about 2300-2500rpm.
IDIBRONCO
IDIBRONCO
You might get lucky and be able to see a crack (cracks?) in the flexplate, then again maybe not. If that doesn't work, then you'd have to at least slip the transmission back a few inches. Far enough that you can see the entire flexplate. When I had one break, years ago on a gas engine, it broke out a circle around the bolts that held it to the crankshaft. I couldn't see that until the transmission was out of the way. All I knew was that the truck stopped moving at a stop sign.
I cant see any visible cracks and it doesnt appear to be wobbling when the motor is running. Definitely hear a light scraping noise from that area when running at idle. However I dont hear it when its first started and the engine is cold. Has to be warm to hear it...
IDIBRONCO
IDIBRONCO
As someone who isn't anywhere close to being an expert on transmissions, I'm pretty sure that it's not the flex plate. I don't see how engine temperature or transmission temperature could affect flex plate noise.
That's why I was thinking tc on it's way out. Truck has to run for ~10 min before before I hear anything. But I'm no transmission expert either so I'd look into any possibility. Its confusing because even with the noise the truck runs and shifts good.
