Trans filter change

This is the wife's truck. It is a 2000 Silverado 1500 with a 5.3L with around 159k miles. What type trans fluid is needed and how many quarts is needed to refill the trans after replacing the filter.

If not a Allison transmission it came with dexron 111 in it.
Which is no longer being made.
But GM has come out with the new synthetic Dexron 6 fluid.
Changes it from regular dex 111 fluid to synthetic.
They say Dexron 6 mixes good with the dexron 111.
A lot of them is changing over to the Dex 6.
Has it ever been changed before?
Any problems with transmission at this time?
Proceed with caution on changing fluid on a high mileage transmission.
Depending on what transmission and what oil pan it has and how long and much you drain out.
It can take from 5-7 qts for filter change and up to 11-13 for full change.
I always check how much comes out and add that much back and the top off when hot in park.

Thanks for the info, I have changed the fluid a very long time a go. So this time around I want to change the filter too. I know that the trans pan has a drain plug. So I do not know if that matters.

If the oil pan drain plug will come lose without a lot of hassel ttake it out and let drain in a big pan or big bucket.
Saves a lot of mess.

But some of the drain plugs are real hard to get lose.
If so just get a bigger drain pan and drop the transmission pan.

For a big pan I use the end of a 55 gallon drum but some fluid still hits the floor.

As to the kind of fluid do not use universal fluid or fit all or additives.
A few places may still have dexron 111.
Carquest still has mercon/dexron.
As far as Dexron 6 goes it will mix with your old fluid but on a high mileage transmission that has and is made for Dexron 111 I stay with the it or go mercon/dexron fluid,

Good Luck.

Thanks for the info, I have changed the fluid a very long time a go. So this time around I want to change the filter too. I know that the trans pan has a drain plug. So I do not know if that matters.


your vehicle with the deep pan should take 5qts of DEXRON VI. this is the replacement fluid now required for your transmission. DEXRON III should not be used as this was found by GM to be causing failures.

Using dexron III now produced may not be what it was when GM was the licensing manufacturer ..

my drain plug was installed from factory with loctite. I had to drop the pan the first time with it full .. then using a torch heat the plug to the red point then with a 6 pt socket loosen..

using a rubber gasket is worth the extra cost, it can be used again if torqued correctly to about 7ft lbs.

If the fluid is looking very dark/off color having the drain plug to replace fluid again is worth the effort to get the drain plug functional.