# Transmission Fluid Amount. New conflicting information.



## 06goatm6 (Dec 5, 2008)

I just changed the rear diff fluid and transmission fluid in my car last weekend. The rear end went as planned, drained out the lower hole, filled through the fill plug and somewhere between 1.5 and 2qts fluid started coming out, no surprise there. 
But when I did change the trans fluid after draining and filling through the backup lamp switch something didnt make sense. On any trans I have ever worked on you only fill to the level of the fill hole and then your done. I got to thinking where does this extra .6 quarts of fluid come from? Well I called my friend who runs the service shop at the local GM dealer and this is what he told me. "The transmission in the GTO is installed at a steeper angle and requires more fluid for one of the bearings to be properly lubricated. The procedure for filling is to remove the backup lamp switch and fill until it reaches the bottom of the hole." This is per GM database instructions.
I also have access to All Data Pro Online through work and it states the same procedure. I poured all 5 quarts of the synchromesh I bought into the trans and it was still short of the back up lamp switch. Who came up with this 4.6qt value? And has anyone filled all the way up to the backup lamp switch level? Will this be too much fluid and cause any seals to blow out? How much fluid does it take to reach the backup lamp switch hole?
I would like to get this figured out once and for all so we all have the correct information. Mine has 5qts in it right now, but I wont be driving it for a few more months so Im not in a big hurry to find out, but I do need this solved before it gets plates on it.


----------



## 06goatm6 (Dec 5, 2008)

Straight from the manual......
How to Check Manual Transmission
Fluid
Because this operation can be difficult, you may choose
to have this done at the dealership service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading.
Notice: Too much or too little fluid can damage
your transmission. Too much can mean that some
of the fluid could come out and fall on hot engine
part or exhaust system parts, starting a fire.
Too little fluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission fluid.
Check the fluid level only when your engine is off, the
vehicle is parked on a level place, and the transmission
is cool enough for you to rest your fingers on the
transmission case.
Then, follow these steps:
1. Remove the reverse light switch.
2. Check that the lubricant level is up to the bottom of
the switch hole.
3. If the fluid level is good, install the switch and be
sure it is fully seated. If the fluid level is low, add
more fluid as described in the next steps.
How to Add Manual Transmission Fluid
Here is how to add fluid. Refer to the Maintenance
Schedule to determine what kind of fluid to use. See
Recommended Fluids and Lubricants on page 6-12.
1. Remove the reverse light switch.
2. Add fluid at the switch hole. Add only enough
fluid to bring the fluid level up to the bottom of
the switch hole.
3. Install the reverse light switch. Be sure the switch is
fully seated


----------



## Jaybird48 (Feb 25, 2021)

06goatm6 said:


> Straight from the manual......
> How to Check Manual Transmission
> Fluid
> Because this operation can be difficult, you may choose
> ...


Is it the same for an 04 gto?


----------



## CheysGoat05 (May 5, 2021)

06goatm6 said:


> I just changed the rear diff fluid and transmission fluid in my car last weekend. The rear end went as planned, drained out the lower hole, filled through the fill plug and somewhere between 1.5 and 2qts fluid started coming out, no surprise there.
> But when I did change the trans fluid after draining and filling through the backup lamp switch something didnt make sense. On any trans I have ever worked on you only fill to the level of the fill hole and then your done. I got to thinking where does this extra .6 quarts of fluid come from? Well I called my friend who runs the service shop at the local GM dealer and this is what he told me. "The transmission in the GTO is installed at a steeper angle and requires more fluid for one of the bearings to be properly lubricated. The procedure for filling is to remove the backup lamp switch and fill until it reaches the bottom of the hole." This is per GM database instructions.
> I also have access to All Data Pro Online through work and it states the same procedure. I poured all 5 quarts of the synchromesh I bought into the trans and it was still short of the back up lamp switch. Who came up with this 4.6qt value? And has anyone filled all the way up to the backup lamp switch level? Will this be too much fluid and cause any seals to blow out? How much fluid does it take to reach the backup lamp switch hole?
> I would like to get this figured out once and for all so we all have the correct information. Mine has 5qts in it right now, but I wont be driving it for a few more months so Im not in a big hurry to find out, but I do need this solved before it gets plates on it.


I know this is way old now but if your still on here what did you fidgure out?? I have a 05 automatic and wanna change it for the first time. Any advice?


----------

