best fluid for '99 T56?
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From: Redmond WA
best fluid for '99 T56?
I had my tranny rebuilt, but now it has this annoying whine in 1-3 from 2k rpm+. I don't know what the shop filled it with, but is this something that the right fluid can fix, or does it need more than that?
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The shop owner wants to try a different fluid that he's calling "Impact" by MTL. I did some googling and it looks like MTL is a Red Line brand, but there's nothing made by them by that name. He says it is a heavier oil that can even quiet a ZF. Anyone heard of this before? I'm concerned about doing damage to those paper blocker rings in the early T56's with any other fluid, plus I also feel like it's trying to cover up something that is wrong, like adding thick oil to an engine with rod knock. He doesn't seem to think it's a problem worthy of removing the trans to fix it, because he says his hearing's not so good and he can't hear anything and doesn't understand why I'm making a fuss about it.
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Of course its not worth removing to him. Its not his car, and he doesnt get paid for it. Having to put non-called-for fluid in to fix a problem lets you know it is not correct. Besides, that wont fix it. Its just a temporary fix that he hopes will quiet it down long enough to get you off his back. Then when it returns, it will be too late to get the work done at no cost. My opinion anyway.
Burning Brakes
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From: Grand Rapids MI
If possible, a high quality video could possibly help us diagnose the sound more accurately. We can not be SURE it is the transmission, really. Could be a pilot bearing, TT bearing, diff, etc. The TT acts like a megaphone, and sounds can sound like they are coming from a totally different location than where they originate. Perhaps getting under the car on a lift while it is running and using a stethoscope could help you make sure you have the source.
I would GUESS the trans is shimmed improperly, but that is based only on the assumption that the noise immediately after the rebuild is not coincidence, combined with the assumption that the person that rebuilt it doesn't do quality work. Both assumptions, both could be very wrong.
Jack
I would GUESS the trans is shimmed improperly, but that is based only on the assumption that the noise immediately after the rebuild is not coincidence, combined with the assumption that the person that rebuilt it doesn't do quality work. Both assumptions, both could be very wrong.
Jack
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Burning Brakes
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From: Grand Rapids MI
Burning Brakes
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From: Grand Rapids MI
My reason for delving deeper is that in order to do a transmission, you have to remove the input of the propshaft from the pilot bearing, remove the output of the trans from the diff, remove the input of the trans from the TT, etc etc etc.
A lot of things could have been damaged and now cause a whining noise.
Jack
A lot of things could have been damaged and now cause a whining noise.
Jack
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