th400 noise,no power at startup then fine????

[akraven]

I have a 90 Suburban that when it starts up has a "whirring" type noise like low fluid and if put in gear doesn't move. It lasts around 15 secs in the summer and 30 secs in the winter then is absolutely fine. It only does it when it been sitting for a day or two. I had a torques convertor go bad about two years ago and had it checked over while that was swapped and tranny shop reported the rest of it was in great shape. Fluid level is fine and fluid looks clean red with no discoloration or burnt smell.
Any ideas would be appreciated before I go to a shop.

 

[chengny]

I have a 90 Suburban that when it starts up has a "whirring" type noise like low fluid and if put in gear doesn't move. It lasts around 15 secs in the summer and 30 secs in the winter then is absolutely fine. It only does it when it been sitting for a day or two. I had a torques convertor go bad about two years ago and had it checked over while that was swapped and tranny shop reported the rest of it was in great shape. Fluid level is fine and fluid looks clean red with no discoloration or burnt smell.
Any ideas would be appreciated before I go to a shop.

Check that the filter pick-up tube is tightly seated in the valve body and that the o-ring (s) is/are good. You know how loose those filters are - I always think they can work the tube out of its seated position in the VB.

 

[Charlie]

 

[akraven]

Thank you Chengny I will give that a try this weekend.
Thank you Charlie. Been lurking for awhile and finally had something to post.

 

[trukman1]

Disclaimer: I'm no tranny expert but my TH400 had a similar problem after I installed a shift kit. My buddy told me there is a plunger on a spring that goes into the valve body (told you I'm no expert) and to take it out, run some ultra fine sandpaper VERY lightly around the edge of the rubber "cup" and it would stop that. He said some of them don't move easily. Like I said before, I'm no expert so try it at your own risk. Might be worth a try. You can at least make sure it's moving in it's bore smoothly. Hope this helps.

 

[akraven]

Well the holiday weekend was too busy with family to get anything done. trukman1 do youknow which plunger that might be? I too am no tranny expert and wouldn't want to blindly want to wander around in there. Thanks!!

 

[HotRodPC]

Check that the filter pick-up tube is tightly seated in the valve body and that the o-ring (s) is/are good. You know how loose those filters are - I always think they can work the tube out of its seated position in the VB.

Did you ever get this fixed @akraven ??? I'm with Chengny on this. It does sound like it's dropped the filter and or tube, or not sealing at the O ring tube.

 

[akraven]

Resurecting this post to tell you that the tranny did eventually fail. Sorry to take so long to get back to this. According to the tranny shop it was a failing pump making the noise.

 

[Vbb199]

I've never seen this post until now, but that was my immediate assumption. Failing pump

Sent from my SM-G965U using Tapatalk

 

[akraven]

I've never seen this post until now, but that was my immediate assumption. Failing pump

Sent from my SM-G965U using Tapatalk

Where you when I needed you Vbb199?

Lucky it failed in town not out on the road so all is well other than my wallet. Had them use HD parts and added a temp guage.

 

[Vbb199]

Where you when I needed you Vbb199?

Lucky it failed in town not out on the road so all is well other than my wallet. Had them use HD parts and added a temp guage.

I don't belive I was a member when this was posted haha.
But I'm glad you got it taken care of!

Sent from my SM-G965U using Tapatalk