Could this be a bad transmission pump?

[mountie]

You need to raise it on a lift.....
SOMETIMES, by taking it to a legit transmission shop, and ask an "old school" tech to listen, maybe the sound is familiar to the mechanic and can steer you in the right direction.

 

[mountie]

I don't know the difference of the transmissions, but, in my 1988 GMC C2500, the forward pump failed. It made a 'similar' but MORE OF A SOLID sound, for 10 minutes, then immediately, the 700R4 went into a neutral ( no more go )..... ( The forward pump is located behind the 8" cover, where the torque converter attaches.)

 

[rockola1971]

Sounds like a torque converter bolt backed out and its head is striking something or possibly a rock jumping around in the area of the torque converter. Is the plug still in place?

 

[OR VietVet]

I would want to look up in the flex plate mount bolts area, for cracks in the flex plate. Should be ruled out as a source of the noise.

Or, where the torque converter engages at the front pump area.

 

[rockola1971]

I would want to look up in the flex plate mount bolts area, for cracks in the flex plate. Should be ruled out as a source of the noise.

Or, where the torque converter engages at the front pump area.

Yup a cracked flexplate will mimic the noise in the vid too. The noise comes from the flexplate distorting outward around the crack and the nearest torque converter bolt head strikes the bellhousing area.

 

[triker97]

You need a stethoscope to pinpoint exact location.

It's a good thing I bought one a while ago, are there any certain points to listen were it would tell me what it could be? Like for example listening to point A it could be the pump
Listening to point B it could be a a worn gear
Point C could be whatever else

 

[OR VietVet]

My stethoscope had a pointed metal probe that allows for tight places and also a hollow tube with a coned cup to seal the listening area:

Amazon.com

Another way would be to remove the inspection cover and look in there for the loose bolts or cracks. A bore scope is great to have. I wish I had one.

 

[Jimmyy]

Amazon.com

 

[triker97]

Hopefully @NickTransmissions can chime in with help.

In the future, it is always best to post what year, make and model vehicle you have. Or is it a secret?

So I've been doing some research but what do you think the chances are that the noise could be a worn parking pawl?? My truck does roll a little after putting it in park and there have been times where it's hard to get out of park. @NickTransmissions I don't know if you've seen the video, any help or advice would be greatly appreciated

 

[triker97]

My stethoscope had a pointed metal probe that allows for tight places and also a hollow tube with a coned cup to seal the listening area:

Amazon.com

Another way would be to remove the inspection cover and look in there for the loose bolts or cracks. A bore scope is great to have. I wish I had one.

I have the same stethoscope and I'll try to pinpoint the noise more this weekend, hopefully I'll be able to get a video up for yall