First time for an ALL FLUIDS CHANGE - Suggestions?

[kasedian]

Within the next month Im going to attempt an "All fluids change" on all my vehicles. I have a 2008 Silverado 1500 4x4 with the 5.3. A 1999 Chev. Blazer 4x4 with the 4.3 V-6. And a 1993 Silverado 1/2 2wd with the 5.7(350).
Im using QS 5-30 sythetic in the 2008, and QS 10-30 conventional in the other two.
Anways, I want to keep everything synthetic on the 2008 Silverado. And the other two, im not quite as particular on.
I need recommendations for the front and rear diffs, trans. fluid, and the transfer case fluid for the 2008 Silverado.
Also, for the 1999 Blazer and the 1993 Silverado I need recommendations too, but not necessarily synthetics.
All the vehicles are daily drivers, if that makes a difference. I live in Kansas, where the summers are hot(+100) and the winters can get quite cold(0-10).
The mileage: 2008 Silverado - 49000
1999 Blazer - 183000
1993 Silverado - 150000
Thanks for your help

 

[Ken2]

Brake fluid--I like Castrol or Valvoline DOT3
Power steering fluid--syn ATF if permitted. Lubegard's power steering fluid or supplement works very well.
Coolant--ask in the coolant sub-forum. There are likely better choices than Dex-Cool.
Engine oil--you're doing good. Nothing special about Shell's QS, and nothing wrong with it.
ATF--your choice of Dexron VI
Diffs & x-fer case--syn is good in those temperatures; follow the book's viscosity recommendations. Which brands are locally available? Amsoil and RedLine are great as always, but local stuff works well and is easy and likely cheaper to get. Mobil 1 is always very good.

 

[Cause4Alarm]

you want to stay with 5w30 if not 0w30 for all three engines. 10w30 flows slower when cold and is no thicker than 5w30 when hot, so the switch hurts not helps...the diffs in all but the 93 take synthetic 75w90, but i would use it in the old truck too. the blazer can go with either dex iii or gm manual transmission and transfer case fluid. the 08 is different....if you have an 'auto' button for 4 wheel drive you HAVE TO use gm auto trak ii fluid, it's the only thing approved for use in it. if you don't have the 'auto' button then it's the same as the blazer.... the diffs in the 08 silverado and the blazer REQUIRE synthetic 75w90, amsoil is my lube of choice and i would use it in the old truck as well...and i like to use amsoil universal atf for transfer cases

 

[SuperDave456]

I'm really digging Maxlife Dex/Merc for my Ford's.
It is Dex IV certified.

The oil you are using is fine.

For Diff's I go full synthetic. Either Amsoil or Redline.

 

[JHZR2]

I think it is smart. BMW M cars do all major fluids at 1200 miles. My chevy truck said to do the LSD fluid at 7500 miles. My front diff, which I didnt do until a few years later, came out with signs of moisture.

The only thing Id say you may not need to do is brake fluid/PSF in the newest silverado... But it is likely smart to dothose too.

Dont forget the transfer case fluids!

 

[kasedian]

Ok. Hows this sound - Ill use Mobil 1 75w-30 synthetic in ALL the diffs. QS Dexron VI for the blazer and old truck, and Mobil 1 synthetic Dexron VI for the 2008. As far as the transfer cases go, Im still lost.
Im planning on getting the supplies locally through Advance Auto, so Amsoil is out.

 

[Turk]

X-fer Case: Yep, have to use GM Auto-Trac II

Front & Rear Diffs: Amsoil Severe Gear

Transmission: Amsoil ATF

P.S Fluid & Brake Fluid: Doesn't matter as much.

 

[kasedian]

OK - Just looked in my owners manuals. The 2008 Silverado says DEXRON-VI ATF for the trans. AND the transfer case. So, I think Ill go with Mobil 1 synthetic in those two.
On the 1999 Blazer, it says DEXRON-III for the transmission, and "Automatic Transfer Case Fluid" (GM Part No. 12378396) for the transfer case. Now I know I can use DEXRON-VI in place of the D-III in the transmission, But what about the transfer case? Is there an equivalent I can use instead of GMs? Thanks

 

[Eric24]

don't use Auto-Trac II in the transfer case use Dexron VI for your silverado

 

[kasedian]

Yeah, I got that. I am going to use Mobil 1 Synthetic ATF on the 2008 Silverado, in the trasmission and the transfer case.

As far as the transfer case on my 1999 Blazer, I think Ill use GM #12378508. Its the Auto-trak II.

 

[hisilver]

After reading the responses, Id like to add a few points.
Dont use a dex VI type fluid in the transfer case. I believe it needs a dex III type fluid (I assume M1 will be fine) because dex VI is thinner than III, too thin for xfer case. GM no longer makes the dex III and now it is labeled as transfer case fluid (pretty much relabled dex III).

 

[kasedian]

Ok. What should I use? The owners manual says to use DEXRON-VI in the transfer case. Its a 2008 truck. Has this been changed since the manual came out? Thanks

 

[hisilver]

If your manual says that then i would go with the manual. Dont mean to confuse you. My 06 chevy truck takes dex VI in the transmission, and dex III in the manual shift xfer case (np 261).
Also, does M1 atf meet dex VI? Just curious. I use Full Syn Valvoline Dex VI in my transmission and it works very well.

 

[Cause4Alarm]

from what i understand gm has updated it's stance on using dex vi in TC's.....they say NOT to use dex vi but manual trans and tranfer case lube, with the auto trak using it's own fluid

 

[kasedian]

Ok. Just stopped up to the GM dealer and talked to the service dept. They looked in their computer, and it showed to use Dexron-VI in the transfer case. I told them I had about 50000 miles on my truck and was changing all the fluids. They tried to talk me into a transmission flush for $150. I was just planning on dropping the pan, and changing the filter. What do you guys think? Is it worth it? Also, about the differentials. He said GM recommends NOT to changes the fluid, UNLESS you have to get in there for another reason. Didnt quite get that one. I alreday purchased some Mobil 1 syn. gear oil to do it. Anyways, what's everybodys opinion? Thanks