A340F Whining (Suspected Front Pump)

Hello everyone. I recently acquired a 2001 4Runner with 544k miles on it with the intent of restoring it. Supposedly the engine and transmission are original.. Paint is in good shape, zero rust, sunroof works like new without leaks, etc.. Still needs a lot of work though. I posted here since I have an A340f question and the 4Runner forums has restrictions on new members making threads.

Anyways. I bought the thing with a decent transmission leak, I was told the front pump. I have yet to go underneath and confirm since it'll take a few hours of degreasing, however everything the seller told me thus far has held up.

Regardless of the leak, there is a whining present. The following is true:

• New fluid and full.
• Whining only during acceleration in drive/reverse.
• Shifts very smooth, both upshift and downshift.
• Alternator recently replaced.

I don't think its engine related since the noise isn't present during idle, deceleration, or revving in neutral. I don't think its one of the differentials since I can hear the whine match the quick rpm adjustment right when the trans shifts. Perhaps its the torque converter but I would think the truck would have more symptoms other than just a whine. I also listened to a couple of bad torque converter videos on this forum and they sound more like grinding or friction related..

I suspect it to be the pump since I can only assume the trans has been run low a handful of times. I have done it once since purchase unfortunately, but it was a mere drive around the block before I realized.

I will grab a video soon.

Please shed any light. I know 01/02 4Runners suffered from planetary gear issues as well but the trans shifts so well I want to believe its just as minor as a pump..

 

Okay so I have some new information.

I noticed that the whine goes away completely in 3rd and 4th in the higher RPMs. The torque converter for the A340 locks up in 3rd and 4th, yes?

With these symptoms would it make sense to suspect a failing torque converter?

My next course of action is to replace the filter and fluid (should have done that already..), but I need to drop the transmission anyway for the leak so I may just address the filter, pump, and torque converter all at once.

Anybody see an issue with my thought process? I'm thinking of finding a reputable shop to rebuild both the pump and torque converter unless some members here can chime in with good aftermarket alternatives that meet or exceed OEM quality and spec. Perhaps a slightly lower stall speed. Still need to do more research on these transmissions, I'm more familiar with the R series (have an AR5 IS300 that I pulled the A650e out of).

@gearcruncher