nitrouscharlie

Any suggections on checking the tranny fluid levels. I noticed a tranny leak in a bubby's auto C5. The leak is fixed but we're unsure as to how much we have lost. And how much to add.

skyavonee

This should help
c5-tech/2738974-diy-procedure-c5-6-speed-manual-fluid-change.html

Chris Stewart

The vehicle must be level with the engine running and the shift lever in the PARK range. (86-122°F)

Remove the transmission plug. Check the fluid level. If necessary, use a small screwdriver as a dipstick.

The fluid level should be even with the bottom of the threaded plug hole.

Add DEXRON III automatic transmission fluid in increments of 0.5 L until the fluid drains from the plug hole.

Toque

I agree...

Toque

nitrouscharlie

Cool guys, thanks. My buddy has a built Roddler Tranny with a Vacuum modulater and he noticed that the tranny was starting to slip a little when going into Over Drive. And when we saw the tranny fluid leak Im thinking that the leak has brought the level down enough to cause it to start slipping...

mickey_7106

exept you might have a hard time finding DEX III (at least in my area) GM moved up to DEX VI.

Chris Stewart

I've been using the walmart brand that's about $10/gallon.

memphis_vette

He needs to know how to check an auto tranny if I am not mistaken?

Bill Curlee

WARNING! CAUTION!!!! If you want to check the C5 automaitc tranny fulid level,,, The ENGINE MUST BE RUNNING with the tranny in park and at the correct operating temp!

If you remove the plug with the engine OFF, fluid will gush out of the plug hole. You can NOT properly fill the transmission without the engine running!!

Here is the procedure directly out of the manual:

--------------------------------------------------------------------

Transmission Fluid Checking Procedure
4L60-E Transmission Fluid Checking Procedure Step
Action
Value(s)
Yes
No

1
Start the engine and allow the engine to idle until the transmission fluid temperature has reached the value specified.
Depress the brake pedal and move the shift lever through the gear ranges, pausing a few seconds in each range. Return the shift lever to the PARK range.
Raise the vehicle on a hoist. The vehicle must be level with the engine running and the shift lever in the PARK range. Refer to Lifting and Jacking the Vehicle in General Information.

Caution
The engine must be running when the transmission fluid fill plug is removed, or excessive fluid loss will occur. Transmission fluid may be hot. Since the actual fluid level is unknown, stand clear when removing the fill plug. Have a container ready to capture any lost fluid. Do not turn the engine off with the fill plug removed, as you can be injured by hot transmission fluid being expelled out of the oil fill opening.


Remove the transmission plug.

Important
The transmission fluid may darken with normal use and does not always indicate contamination or oxidation.


Check the fluid color. If necessary, use a small screwdriver as a dipstick.
Is the fluid color clear red or light brown with no burnt odor?
30°C to 50°C

(86°F to 122°F)
Go to Step 4
Go to Step 2

2
Does the fluid have a burnt odor or a dark brown color?
--
Go to Step 8
Go to Step 3

3
Does the fluid have a cloudy or milky appearance?
--
Go to Step 7
Go to Step 8

4
Check the fluid level. The fluid level should be even with the bottom of the threaded plug hole.

Is the fluid level low?
--
Go to Step 5
Go to Step 11

5
Add DEXRON III automatic transmission fluid in increments of 0.5 L until the fluid drains from the plug hole.

Did you add more than 1.5 L to the transmission?
--
Go to Step 6
Go to Step 11

6
The transmission may have a leak. Refer to Fluid Leak Diagnosis .

Was a transmission fluid leak found?
--
Go to Step 9
Go to Step 11

7
The transmission fluid is contaminated with engine coolant. Repair or replace the transmission cooler in the radiator.

Is the transmission cooler repair complete?
--
Go to Step 9
--

8
Drain the fluid by removing the bottom pan.

Important
A very small amount of material in the bottom of the bottom pan is a normal condition.


Check the bottom pan for any excessive debris.
Was excessive debris found?
--
Go to Step 9
Go to Step 10

9
Repair the transmission if required (in some cases, overhaul may be required).
Flush the transmission oil cooler and pipes and check flow. Refer to Automatic Transmission Oil Cooler Flushing and Flow Test .
Add enough DEXRON III automatic transmission fluid to bring the fluid level to the bottom of the threaded plug hole.
Start the engine and allow the engine to idle until the transmission fluid temperature has reached the value specified.
Depress the brake pedal and move the shift lever through the gear ranges, pausing a few seconds in each range. Return the shift lever to the PARK range.
Raise the vehicle on a hoist. The vehicle must be level with the engine running and the shift lever in the PARK range. Refer to Lifting and Jacking the Vehicle in General Information.

Caution
The engine must be running when the transmission fluid fill plug is removed, or excessive fluid loss will occur. Transmission fluid may be hot. Since the actual fluid level is unknown, stand clear when removing the fill plug. Have a container ready to capture any lost fluid. Do not turn the engine off with the fill plug removed, as you can be injured by hot transmission fluid being expelled out of the oil fill opening.


Remove the transmission plug.
If needed, add DEXRON III automatic transmission fluid in increments of 0.5 L until the fluid drains from the threaded plug hole.
Allow fluid to finish draining out of the plug hole. Install the plug and tighten to specified value. Refer to Fastener Notice in Cautions and Notices.
Wipe any excess fluid from the transmission with a rag or shop towel.
Is repair complete?
30°C to 50°C

(86°F to 122°F)

30 N·m

(22 lb ft)
Go to Road Test Procedure
--

10
Change the fluid and the fluid filter. Refer to Automatic Transmission Fluid/Filter Replacement .
Start the engine and allow the engine to idle until the transmission fluid temperature has reached the value specified.
Depress the brake pedal and move the shift lever through the gear ranges, pausing a few seconds in each range. Return the shift lever to the PARK range.
Raise the vehicle on a hoist. The vehicle must be level with the engine running and the shift lever in the PARK range. Refer to Lifting and Jacking the Vehicle in General Information.

Caution
The engine must be running when the transmission fluid fill plug is removed, or excessive fluid loss will occur. Transmission fluid may be hot. Since the actual fluid level is unknown, stand clear when removing the fill plug. Have a container ready to capture any lost fluid. Do not turn the engine off with the fill plug removed, as you can be injured by hot transmission fluid being expelled out of the oil fill opening.


Remove the transmission plug.
If needed, add DEXRON III automatic transmission fluid in increments of 0.5 L until the fluid drains from the threaded plug hole.
Allow fluid to finish draining out of the plug hole. Install the plug and tighten to specified value. Refer to Fastener Notice in Cautions and Notices.
Wipe any excess fluid from the transmission with a rag or shop towel.
Is repair complete?
Did you drain the fluid?
30 N·m

(22 lb ft)
Go to Road Test Procedure
--

11
Allow fluid to finish draining out of the plug hole. Install the plug and tighten to specified value. Refer to Fastener Notice in Cautions and Notices.
Wipe any excess fluid from the transmission with a rag or shop towel.
Is repair complete?
30 N·m

(22 lb ft)
Go to Road Test Procedure
--

nitrouscharlie

Yes sir, that's correct. And as for the "procedure" if doing the fill. I dont see how tha's possible or even if Id want to try that.It says to bring the car to running temp, and do the fill with the car running. With a hot tranny and even hotter exhaust right there in your face. That sounds rediculous.

Bill Curlee

Thats why soooooooooo many people screw it up. Its a challenging procedure and tough to do properly. Is doing it incorrectly worth a new tranny!!!???

Thats the ONLY way to do it properly. Break out the kevlar gloves and check it correctly.

BC

scottsphoto2

Thanks for teaching me how to check and change the tranny fluid,but i am hoping someone can explain this for me. I have recently purchased my 1st c5. While looking for a gas leak i backed her up on ramps then jacked her up on one side. After doing this 2 times,she started leaking transmission fluid. I was about to take it to the shop when a friend told me that it may have just leaked because of me jacking it up. So i let it set a few days and took it up the road. Sure enough,when i got back there was no leak. Can someone tell me if i done wrong by jacking a vette up like this? Also now i notice a noise in the passenger rear wheel when i am slow rolling.(most of the weight of the car was on this wheel while it was jacked up) Could i have damaged something else by having her up on ramps and jacked up on one side?

Dale002

It's not the big of a deal to do if you have correct jacking equipment.
The trick is to have it level and that's almost impossible with out a lift or drive on ramp where all four wheels are on the ramp.
If you don't have neither,I would suggest taking it to a shop and have them service it.
I've never had much luck with slipping trannys,usually once you feel them slipping it's too late.
Best of Luck.