DFM C5 Z51

Rookie C5 owner; I hope this belongs here, not in Tech, but might be Tech later. Got my 6900 mile 2002, LS1, 6spd. Tires 2 yrs. old, so drove it 400 miles home. Everything works perfectly. No contact with 2 previous owners. 1st 3500 miles and 18 years was original owner. Next owner who drove it for 1yr. or so put the next 3400 miles on. All I know is dealer service before and after last owner. Tires, belt or two, tire pres. sensors, etc. Mobil 1 oil changes each side of last 3400 miles.

So I think of coolant, transmission/rear axle, brake fluid, what else. With no history and low miles, I assume nothing was changed. (I notice radiator hoses are dated to build date). I will try to do some myself if I can get ramps or lift, over time.

I know there will be many opinions...for the record my feeling is coolant first, (with thermostat & hoses?) then trans/axle. Perhaps fluid changes are not first priority. How would you C5 owners approach this? Thanks in advance.

roegs

I purchased my 2002 a few years ago with 19k miles on it. Somewhat similar concerns about fluids and knew for sure that coolant had never been changed. I went in this order..

- Coolant
- Brake Fluid
- Transmission fluid (filled with Amsoil Torque Drive)
- Multiple Clutch Fluid swaps with Ranger Method

My hoses and thermostat seem to be just fine. Best tool I've purchased to date is a Quickjack. Bought mine used and love it.

lobuzz311

I think a full set of fluids is cheap insurance to make sure it will keep running nicely for you.
Yes, the fluids are not so “used” at that mileage, but they sure are OLD.

Here’s what I immediately did when I got my C5Z last year: (in no particular order since I did it all at the same time)

1. Engine Oil / Filter:
< 7 quarts Amsoil Signature Series 5W-30 Synthetic Motor Oil
WIX 51042 Oil Filter

2. Rear Diff Fluid:
< 2 quarts Amsoil SEVERE GEAR 75W-90 + ACDelco LSD Additive

3. Trans Fluid:
< 4 quarts Amsoil Signature Series Multi-Vehicle Synthetic Automatic Transmission Fluid

4. Clutch:
< 1 quart Motul RBF600 Dot 4 Fluid

5. Brakes:
< 2 quarts Motul RBF600 Dot 4 Fluid

6. Power steering:
< 2 quarts Amsoil Synthetic Power Steering Fluid

7. Coolant:
Prestone Dexcool 50/50 premix

The nice thing about doing it all at once is the Amsoil discount club. I bought all my Amsoil stuff direct and the year of discount immediately paid for itself and then some.

hyperv6

I just went trough this.

Did brake fluid, belts tires, oil and tested the anti freeze as it tested new.

tranny and diff fluid just need checked as they are long term products. As long as it was not in a flood you are fine.

Brake fluid can be tested for moisture and odds are it will need changed. Clutch fluid needs tested if you have one.

schmuckingham

The Severe Gear already has the LSD modifier in it.

lobuzz311

Yeah, except there was some wording on the packaging that it was fine for “some LSDs” and that others required their LSD additive.
I just got the factory GM stuff to be 110% safe and make sure I didn’t have any diff whine.

yellowGS

I purchased my 2003 last summer with approximately 68000 miles. Two owners previously. The woman who owned it before me kept it in nice clean condition, but maintenance was lacking. Here’s what I have done to date begin last June, and my plans for the next 12-18 months Corvette Maintenance Log:

Replace suspension control module - Done August 2022

Rear differential drivers side repair - Done September 2022

New sway bars and bushings C6 Z51

10339124 Rear Done September 2022

15241135 Rear bushings Done September 2022

New Hotchkis sport front sway bar, part #2284F Done June 2023

New Moog sway bar end links Done September 2022

Replace shocks:
Blistein 24-029759 front, 24-029766 rear. Done September 2022

Replace spark plugs and wires: Done September 2022

Spark Plugs, ACDelco 12621258
Wire Set, ACDelco 89017270

Flush and replace fluids (radiator, transmission, differential) - Done September 2022

Replace thermostat - Done September 2022

Replace belts, tensioners and idler pulley’s. Done August 2022

New battery - Done August 2022

Clean and seal grounds - done July 2022

Oil change - done July 2022 & June 2023

Clean radiator and ac condenser grills. Done May 2023

Install catch can - Done September 2022

New tires and TPMS sensors - done August 2022

New DRL assemblies Done May 2023
10301356
10301357

New headlight bulbs - Done September 2022

Install Bluetooth harness for radio - Done September 2022

New seat foam and leather covers Done April 2023

Install leather brake and e boot covers. - Done September 2022

New rear brakes, rotors and pads
Power Stop K1563
Done June 2023


To do for 2023/24

New brake and power steering fluids

Replace outer tie rod end links

Replace ball joints

Replace radiator hoses

New front brakes, rotors and pads
Power Stop K1559

ICT Billet coil pack brackets, part #551642

Change valve springs to LS6, part # GM12499224

Fel-Pro valve stem seals, part #ss71039

BTR, Chromoly LS1 pushrods, 7.4” long, 5/16” diameter 0.080 wall

BTR, LS Rocker arm trunnion upgrade kit, part #55100-01 Comp Cams trunnion tool, part #54702-TL

Replace harmonic balancer and pin kit

DeWitts radiator and fan

Install new Pioneer touch screen stereo

AVH-3500NEX

Replace passenger side door speaker

c5arlen

Would you repeat that please?

MWWarlord

Welcome to the forum! Fluid changes are a good idea. The t-stat should be fine. As far as the radiator hoses, I would replace or not based on condition. If they look good and are still supple, then no need to change. Tires are the big thing on a car like that, and yours are only 2 years old, so no issues there. Swap all the fluids, then drive and enjoy!

Don't forget to SAVE THE WAVE!!

DFM C5 Z51

@yellowGS , at my age, I could not live enough to do what all you have to your C5. Hopefully my low miles will mean most of that will never happen. All of you have given me plenty of info on where to start.

Something I had not thought of was mentioned as fluid checks or analysis of some fluids. Where have you had that done? When I was an active farmer, I always had engine oil on most machines analyzed every oil change by John Deere, or another independent lab. I never had any other fluids analyzed, so that is something I might be interested in.

Vader_C5

I just picked up a 2003 with 31k miles and no service history, the gentleman was 96 years old, so I wasn't worried

Anyway, I am going to change out the diff, trans, and steering fluid this weekend for good measure. I will get the coolant and brake done when I do brakes after the summer.

For any C5, I would tell anyone to change their fluids; I also did the same on my 1999 with 100k miles previously.

Vetteman Jack

Moving this to C5 Tech since it involves basic maintenance on the car. Congrats on your C5 too.

acroy

As others have mentioned, full flush of all fluids is not a bad idea. I'd not bother with any fluid analysis.

grinder11

Just change everything. Then you have documentation, and peace of mind....

grinder11

LMAO!!!!

DFM C5 Z51

I am leaning toward doing the coolant, transmission, and differential first. Easiest for me to do myself in my shop, once I decide on ramps and or lift. I may get quote from dealer on doing brake fluid and clutch fluid. Power steering I could probably do. Thanks.

Vader_C5

I had my fluids changed at the dealer on two occasions, most Chevy Dealers have a dedicated Corvette Tech