LT1

[Craig]

Hi guys,
Well just got a '93 Corvette conv with a LT1/Auto tranny.
59K on the clock. Mobil 1 since new.

This engine has been overfilled by the dealer for at least the
last few years. Six qts M1 when it specs 5 with filter. Dipstick
was way over when I got it home so I looked closly at the
receipts given to me by seller and sure enough they put
6 qts in the engine every time. (Idiots)

As I noticed some blowby on the valve cover I was thinking of
doing a Auto Rx treatment. I have already changed over to the
correct amount of Amsoil HDD S3K with new EaO filter. Should
be no problem with a Auto Rx treatment right? I will use the
group III Amsoil for the rinse. If you guys don't think this is
necessary please let me know.

I am also considering the LC20 product.

The tranny just received a entire flush with Amsoil ATF so
I am going to leave that as is for now.
Is the Auto Rx tranny tx the same as the engine but just
in a different bottle?

What think you?
Thanks,
Craig

 

[GMBoy]

Yeah - I hate hearing stories like this. I can't believe that these guys never check the oil after changing it! Overfilling can be worse than underfilling. But I really doubt any harm was done unless the oil did not meet the GM standard for your Corvette. All Lt1's came with Mobil 1 from the factory which is one reason its all I ever use. I have a 94 Corvette LT1/auto combo and its a bullet proof drivetrain let me tell you. But anyway - my oil changes take 4.75 qts to be exact on the stick. Best of luck with it and if there is one weak link it;s the opti-spark distributor system. Yours has probably already been replaced.

 

[Craig]

After reading all the excellent posts on AutoRx I added it
to both engine and trans today.
I will use Amsoil group III oil for the engine rinse.
Then back to Amsoil HDD S3K 5W-30.

Is the tranny rinsed like the engine?
If so what dino ATF should I go for.
It will immediately go back to the Amsoil
ATF in the end.
Thanks,
Craig