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I need to change all the fluids out on my 2004 Vette I inherited from my dad so I have a proper basepoint to move on from. What I would like to know is what kind of brake fluid and gear oil (manual transmission) you have used and have proven themselves to be a reliable investment. I'm running everything stock at the moment except after market exhaust, K&N CAI and a basic tune when those were installed. I assume prestone dex-cool 50/50 will be okay for coolant unless there is a better option available? Being it's an older car I'm wondering if there are things that would work better for this car. Currently at about 31k miles. Thank you for your time and I am open to any and all suggestions
Welcome, Levi, and best of luck with your C5! On my previous '99 and '03, I used Amsoil for everything - oil, brake, coolant, clutch, transmission, differential, and steering. I bought all of the fluids and had the Corvette Tech at my local dealership (Paramus Chevrolet) change everything.
Amsoil is fine, check each brand and application you look at to be 100% synthetic. I use Mobil 1 full synthetic for engine, transmission and rear drive. I don't see full synthetic Mobil 1 power steering fluid on the Mobil 1 list of products. I have long used Red Line full synthetic in all my cars with hydraulic power steering. The advantage of full synthetics over petroleum based fluids is much better resistance to oxidation and less forming of deposits at high temperature. Drove two grocery getters to 230,000 miles on synthetics, no deposits and they ran great at 230,000.
I used GM 10-4034. Some here say there is a better GM fluid to use, according to a GM Performance dealer, Scoggin Dickey, in Lubbock, TX. I called the local Chevy dealer, and they recommended the 10-4034. Which dealer you believe is up to you. I have 35,000+ miles on the 10-4034, no issues so far, with almost 141,000 miles on the car. I've also done more than a few burnouts at the strip. All good.......
Plenty of high quality full synthetic engine oils around these days - back in the early days of the C5 this was not so. Any of them will do the job. I am currently using Costco's own brand synthetic; a lot cheaper because I am not paying for anyone's marketing department.
Manual transmission, per the manufacturer (Tremec) and GM, needs the "old" GM Dex III and definitely not the newer Dex VI blend, which GM warned via a tech bulletin can damage older manual transmissions. Dex IIII spec lubes are generally sold as "Dex Merc" at your local parts store, and will be labelled for older GM transmissions. I use Valvoline's Dex/merc, about $18/gallon from Walmart among others. Lots of years and lots of miles (I've owned my C5 from new) and no issues.
Rear end: Again, if it meets GM's quoted viscosity ratings (75/90), run any name brand lube. Mine has had Mobil 1 in it for many years now.
What you need to do is find the fluids that meet or beat the GM specifications.
Many fluids may work but you want to find the most recent specifications. As with time the numbers change to new levels as better products come.
Many over think this and treat this like arguing over politics and religion.
This is more than just about being right but making sure you put in fluids that are up to the higher levels that the. Corvette is capable of. Some products are the same as other vehicles some are not. Also some year take different needs.
So many things work but still may not be what is really recommended as the primary product.
Plenty of high quality full synthetic engine oils around these days - back in the early days of the C5 this was not so. Any of them will do the job. I am currently using Costco's own brand synthetic; a lot cheaper because I am not paying for anyone's marketing department.
Manual transmission, per the manufacturer (Tremec) and GM, needs the "old" GM Dex III and definitely not the newer Dex VI blend, which GM warned via a tech bulletin can damage older manual transmissions. Dex IIII spec lubes are generally sold as "Dex Merc" at your local parts store, and will be labelled for older GM transmissions. I use Valvoline's Dex/merc, about $18/gallon from Walmart among others. Lots of years and lots of miles (I've owned my C5 from new) and no issues.
Rear end: Again, if it meets GM's quoted viscosity ratings (75/90), run any name brand lube. Mine has had Mobil 1 in it for many years now.
do you know where I can find a copy of that bulletin, à GM tech told me that the Dexron VI is what I must put in my Z06 transmission if I can find it I’ll get back to him and have it read. Thank you
do you know where I can find a copy of that bulletin, à GM tech told me that the Dexron VI is what I must put in my Z06 transmission if I can find it I’ll get back to him and have it read. Thank you
I did some searching on this a while back. If no one posts a link to the TSB, I recall it was easy to find with search terms like “dexron vi technical service bulletin”.
I also recall reading something about compatibility testing was not completed at the time of the TSB. I never did find GM literature that said directly that dexron vi was OK for GM vehicle manuals that were spec’d with dexron iii.
Why take a risk when there is a GM manual transmission fluid.
The OEM stuff works well, but you will find a number of other brands that do very well also.
2004 C5 fluid change info
