Replacing The Gear Oil

[solarjustin]

I'm going to replace the gear oil on my 04 with 60k miles. It has never been done before on this truck. Right now I'm leaning towards the Amsoil but wanted to see what you are all using and how you like it.

 

Thanks

[txab]

.

[Hammer2785]

I've used both Mobil 1 synthetic gear oil and Lucas Oil gear oil in both front and rear differentials.

[Sir Dan]

Amsoil would be my first choice and Mobil 1 second. Both are very good and very easy to find at local stores, but Amsoil has proven to be a winner as far as I'm concerned. I started running it in my Harley after using their Screamin' Eagle full synthetic for years. Now the motor runs 20 degrees cooler and much smoother. That says alot for me!

[solarjustin]

and how much do I need?

 

2004 2wd with the 3.42 10bolt.

[txab]

It'll take 2 qts. for sure and probably a little of a 3rd qt. I know on my '04 (3.73), 2 put it right at the correct level. YMMV though. If you end buying something local and you don't need the 3rd qt. you can always return it.

[C. Charles Hahn]

I used to run exclusively Mobil 1; this time around though I put Royal Purple in and I honestly think it does a better job than my M1 ever did.

[Spurshot]

I've never had any rear axle problems (or front on 4wd) using anything from Sta-Lube to Mobil 1. Frankly, I can't tell the difference. My El Camino had half a million miles on the stock rear axle and mostly Sta-Lube in it that was only changed a couple times and it had engines in excess of 400 hp in front of it. Sta-Lube has to be the cheapest stuff money can buy. I run Mobil 1 now, because it's in the stores.

[REV353]

Now days I don't think it matters as much. I have good luck with Amsoil just like others have had good luck with other brands. I did check my mileage and driving before I changed all of my fluids to Amsoil, then switched and I still 13 months later have not noticed even a 1/2 mpg increase, thats what I was hoping for. The truck will make it to 300k on standard oil

[Spurshot]

My experience with the El Camino was from about 1980 to 1998. Gear metallurgy in GM products hasn't changed much if any since then. Even if it did, what more could we ask for? The rear axle will probably outlast the truck, if it isn't damaged from abuse.

[Bish]

Amsoil would be my first choice and Mobil 1 second. Both are very good and very easy to find at local stores, but Amsoil has proven to be a winner as far as I'm concerned. I started running it in my Harley after using their Screamin' Eagle full synthetic for years. Now the motor runs 20 degrees cooler and much smoother. That says alot for me!

 

+1 Amsoil first then Mobil1 for me.

[redvett]

Here is a list of Capacities

 

2004 CHEVROLET TRUCKS 5.3L 8-cyl Engine Code [T]

 

CAPACITIES

Engine, with filter..........6.0 quarts[1]

Cooling System, W/ FR & RR AC Initial Fill..........16.0 quarts

Cooling System, W/ Front AC Initial Fill..........14.0 quarts

Automatic Transmission, 4L60-E Initial Fill..........5.0 quarts

Automatic Transmission, Total Fill

4 speed 4L60-E..........11.0 quarts

Differential, with 8.25 ring gear Front..........3.0 pints

Differential, with 9.25 ring gear Front..........3.2 pints

Differential, with 10.50 ring gear Rear..........5.5 pints

Differential, with 11.50 ring gear Rear..........7.6 pints

Differential, with 8.60 ring gear Rear..........4.2 pints

Differential, with 9.50 ring gear Rear..........5.5 pints

Transfer Case,NP8..........4.0 pints

Transfer Case,NR3/NR4..........3.0 pints

Transfer Case,NVG 246-NP8..........4.0 pints

Transfer Case,NVG 261-NP2..........4.0 pints

Transfer Case,NVG 263-NP1..........4.0 pints

[thearborbarber]

Amsoil Severe Gear oil is top shelf stuff.

[C-Hawks]

How do you tell which gearing you have?

 

Here is a list of Capacities

 

2004 CHEVROLET TRUCKS 5.3L 8-cyl Engine Code [T]

 

CAPACITIES

Engine, with filter..........6.0 quarts[1]

Cooling System, W/ FR & RR AC Initial Fill..........16.0 quarts

Cooling System, W/ Front AC Initial Fill..........14.0 quarts

Automatic Transmission, 4L60-E Initial Fill..........5.0 quarts

Automatic Transmission, Total Fill

4 speed 4L60-E..........11.0 quarts

Differential, with 8.25 ring gear Front..........3.0 pints

Differential, with 9.25 ring gear Front..........3.2 pints

Differential, with 10.50 ring gear Rear..........5.5 pints

Differential, with 11.50 ring gear Rear..........7.6 pints

Differential, with 8.60 ring gear Rear..........4.2 pints

Differential, with 9.50 ring gear Rear..........5.5 pints

Transfer Case,NP8..........4.0 pints

Transfer Case,NR3/NR4..........3.0 pints

Transfer Case,NVG 246-NP8..........4.0 pints

Transfer Case,NVG 261-NP2..........4.0 pints

Transfer Case,NVG 263-NP1..........4.0 pints

[Irv]

Mobil-1 for me, never had good luck with Amsoil engine oil (consumption issues in truck, quad, sled) maybe not an apples to apples comparison but to be honest Amsoil makes me a little nervous