Winter fluid changes to prepare for Spring!

[wyat5357]

I just finished a rear end fluid change on my 02 Z28 (just under 20k miles, though never any fluid changes to my knowledge other than oil). I believe I have the Torsen as I did not notice any springs. As I understand, these do not require the additive since it uses a worm gear as opposed to a clutch which needs reconditioning. Still, I used Mobile 1 Synthetic 75W-90 and a 7oz additive I found at Autozone without really thinking it through. The additive I used is called "Trans-X, posi-trac limited slip gear oil additive" <http://www.crcindustries.com/auto/content/prod_detail.aspx?PN=402508&S=N>. My dad thinks this is a major issue and I should think about doing another rearend fluid change and use the GM additive instead. What do you think? Is it worth it? Has anybody else used this additive?

On another note, when I changed the transmission fluid, I used Valvoline Dex3/Mercon ATF. I know the 6 speed I have calls for Dex3, what is Mercon?

Sorry for the long post! thanks for the help!

[Lucky SOB]

I did the same with my rear this winter - everyone said the additive is not needed, but it won't hurt anything. Since I had already bought it, I put it in with the Royal Purple gear oil.

[BP_Z28]

Mercon=ford

[MP81]

Damn Colton, you didn't need to change any of that! That car is mint!!!

[Fbomb]

I've read that you only need the additive with a nonsynthetic fluid, been running lucas 80-120 in mine for about two years with no additive and no problems. Any dex3 should be fine in the t56 but then again I've heard of synthetic eating up paper blocker rings (2000 and earlier)...I have mobil 1 in mine and again no problems but trans was rebuilt in 07. Not sure if my blocker rings are CF or paper still.

[nascarnate326]

My fluids are pretty good except for the coolant. Unfortunately I see an opti change in the near future so I will tackle that with the opti change.

[JoeliusZ28]

My fluids are pretty good except for the coolant. Unfortunately I see an opti change in the near future so I will tackle that with the opti change.

If you think your coolant is bad change it asap. I know you don't want to be swapping a head gasket over that. Personally id wait until we are clear of a freeze and id just flush it with a garden hose.

[ThreeHonks]

If you think your coolant is bad change it asap. I know you don't want to be swapping a head gasket over that. Personally id wait until we are clear of a freeze and id just flush it with a garden hose.

x2

we left the coolant for too long in our past car, 2000 escort and it actually rusted away a freeze plug and then popped a head gasket

[JoeliusZ28]

Yep, bad coolant is also what ruined my firebird!

[wyat5357]

Thanks for the reinforcement guys! I'm tackling the coolant next, right after I finish the flush in my truck.

[farmington]

Whats the best way to do a thorough flush on a LS1 motor?

[Fbomb]

I drained it and ran water for a week, drained again and filled with fresh water, ran it for a week. Drained and filled with coolant (green). This was during the summer by the way.

[JoeliusZ28]

Whats the best way to do a thorough flush on a LS1 motor?

My method is as follows:

drain the entire system out and dispose. Fill it up with water, run it for a second, drain it again and dispose. By that point most of the coolant should be out so then just park it in the driveway and stick the garden hose in the radiator cap and let it pump water in while the engine is running and the drain valve is open. Let it flush for a while then kill the engine, let it drain, and fill back up with 50/50 or whatever mix you prefer

[shawnc16]

I did the same with my rear this winter - everyone said the additive is not needed, but it won't hurt anything. Since I had already bought it, I put it in with the Royal Purple gear oil.

I'm pretty sure Royal Purple has the additive in it. Don't quote me on it. It would be worth checking into. The additive is to allow slippage. Without it, you can have premature wear

[BP_Z28]

My method is as follows:

drain the entire system out and dispose. Fill it up with water, run it for a second, drain it again and dispose. By that point most of the coolant should be out so then just park it in the driveway and stick the garden hose in the radiator cap and let it pump water in while the engine is running and the drain valve is open. Let it flush for a while then kill the engine, let it drain, and fill back up with 50/50 or whatever mix you prefer

Thats what I do. Always have your favorite beverage near by to kill the time