Need Tranny Help - Can you identify these noises
 

I am hoping that it is not giving up on me. I will try to explain the noises, but it is hard to do with text. The fluid was a little low, but I topped it off today.

It sounds like it is coming from the flywheel or torque converter. In park, it is a racketty sound, like something is loose.

When I go through the gears, I get a different sound at each gear:

Reverse - Higher pitched "grinding"
Neutral - Not much noise
Overdrive - Not much noise
Drive - Not much noise
Second - High pitched "grinding" just like reverse, but a little louder
First - Not as loud as second, but still a little noise

When driving, it sometimes slips from a takeoff going into second. When going about 30, and stopping suddenly, it downshifts roughly, which I thought might have been the torque converter unlocking, but at that speed I wouldn't think so....

Whatcha think, time for a new tranny or is it something minor.

my th 350 did that and within three days of working with it the whole tranny died... listening to it now i think its the torque converter but its too cold for me to fix now.. within a week i should have it brought to the high school for their guys to work on it

Thanks for the info.

I guess if I am going to bother replacing a torque converter, I should just rebuild the whole thing.

When the torque convertors go they will send a lot of debris threw the transmission. Don't forget to flush your radiator transmission cooler and lines really well to get all the debris out.

So does it sound like it is the torque converter?

The increased noise in second and reverse makes me think something else might be going on...

Ok, the "clunk" when braking hard from about 40 mph seems to be more pronounced now.

Can anyone else help identify the problem?

This may be related, but it "clunks" real hard when taking it out of park when parked on a slope (I assume this is the U-joints).

Just a guess, but did you check the torque convertor to flywheel bolts? That wouldn't account for the harsh shifting, but they can bring quite a racket if they come loose. A cracked flywheel can also make a weird noise. Good luck, let us know what you find.

60-66 Nut

I climbed under it real quick and couldn't see the bolts, but I plan on looking tonight (this time with a flashlight).

I should add, the tranny has plenty of fluid and it does not smell burnt.

If it were the bolts, I don't see why the noise would sound different in 2nd gear....

If it is that, does anyone know what size bolts (torque converter to flexplate) they should be?

You're right, does seem strange that the noise would be different in 2nd gear, but like I said I'm just guessing since you said it sounds like it's coming from that area. Hard to know without actually hearing the noise in person. If the convertor is taking a dump, seems like it should make little or no noise once it locks up, but again just guessing. The torque convertor bolts are usually 15mm, when you drop the cover to check them make sure to look closely at the flywheel where it bolts to the crank, if you can see it. I've seen them crack around the bolts.

60-66 Nut

Thanks. It's warm here today and tomorrow (50's) so I am gonna climb under it and look.

Well, I climbed under it. I don't know why I thought I couldn't see the bolts on the flexplate (maybe I was just looking from the rear).

It makes that "grinding" sound intermittently and kinda sounds like a big bug or katydid. (almost like the flexplate teet are rubbing the transmission case for just a second at a time, if that were the case, it would wear the teeth, which it isn't)

I don't see any wobble or anything at the flexplate when it is spinning. I have been told that it sounds like the flexplate is broken where it meets the crank, which sounds similar to what 60-66 Nut said.

Is it a th700r?

Its a lockup torque convertor TH350.

No, it's a 700R4.

:dohh: I thought it was a th350c must have been someone else's I was thinking of.

700 r4 is wat i mean i had the same tranny in my truck and it started making those noises right before it blew on me it blew out 3 gear
from wat i read on here i geuss it cause i always drove in od in the city?!?!
hope i could help