[Savinhillspyda]

Good to know, also, other than being on “level ground” any other tricks for leveling as best as possible?

 

[Savinhillspyda]

Our 9T65's are unique in that unlike most all transmissions that hold all of the fluid in the bottom pan, our's has a expansion tank to hold excess fluid when the trans is hot, then returns it to the sump when the fluid cools and contracts.

This operates much like the expansion tank for the engine coolant.

If you get the fluid as close as you can ( + or - 0.5 quarts) I think this expansion tank will do the rest.

It's all about fuel efficiency. Ever try to run in a swimming pool? It's hard. Same goes for all the spinny bits in the transmission. They want to keep them away from the oil as the volume increases with heat and the level rises.

Pretty smart.

View attachment 9737

So i drained and filled again. Got 5qt’s out of the pan, dumped in 6, and got 1.5 out again. I was on level ground and i added my 160lb Great Dane and a 40lb bag of rock salt to the passenger side to “level” it. Now I’m worried there’s not enough fluid...

 

[AlisoBob]

I wouldn't sweat it.....but the math is kinda weird.

Your first post statues you drained 5 quarts out, put in 6, then lost 1.5 setting the fluid level.
This leaves 4.5 quarts.

Then in the second post, you again drained 5 quarts. Where did this extra 0.5 quarts come from?

 

[repairman54]

If I drained 5 out I would put 5 back in provided there is nothing leaking.
That's how I would do my old '09 Malibu 4 speed with the level plug setup, what came out would go back in with maybe a ounce or two more to cover slight seepage. Worked fine for 190k miles.
Too hard to get a level vehicle without a lift, keep it simple IMO.

 

[AlisoBob]

The inside of a automatic transmission is a very dynamic place. "G" forces in every direction (Acceleration, braking, turning) plus inclines and declines. That "Fluid level" is all over the place while your actually driving.

I think "close counts" as '54 says, and I also think slightly low is better then slightly high. High fluid levels always cause higher temps.

With this "accumulator" function inside the trans.... +/ - half a quart in either direction is probably meaningless.

Keeping clean, fresh fluid in the trans, is still the goal.

 

[Savinhillspyda]

I wouldn't sweat it.....but the math is kinda weird.

Your first post statues you drained 5 quarts out, put in 6, then lost 1.5 setting the fluid level.
This leaves 4.5 quarts.

Then in the second post, you again drained 5 quarts. Where did this extra 0.5 quarts come from?

Yeah i have no idea, unless the expansion tank let go some extra fluid both times

 

[Section9]

Confirm you are performing the test drain plug with the trans temp at IIRC 185-203 Fahrenheit. I believe GM calls for that as that temp range triggers the TCM to release the reservoir perhaps and fill the tranny case, allowing an actual fill test. Service manual states that the reservoir is held back from release until certain parameters are met in the tranny case, one of which might be the temp range.

Also confirm you are performing the test with the engine running when you pull the plug. These are just to check nothing was missed or skipped by you.

I performed the drain and fill (but not the flush yet) on my 2018 HC last month, which was getting the shudder in low gears and lower end of speeds. My tranny temps were reaching 190-200 regularly after 30-45mins of driving and stop and go traffic. At these temps, the shuddering was always present (not to mention, when on first start and pull away from park, it would always slip at about 2-3 or 3-4 gear like clockwork on initial drive).

I drained only 5 quarts from my tranny, filled with six, ran the engine till that temp range (my HC still has the tranny temp on the dash display) and pulled the drain plug. I was only able to drain about 1/3 of a quart out. Garage is perfectly level (even checked with an actual level, as I change my oil as well for years here). Old tranny fluid was dark cherry/brown, but more brown than cherry. I have pics on my other phone, unfortunately.

Drove the car about 100 miles so far, not enough for me to do a flush yet (waiting to hit around 500 miles), so far, no shuddering, no gear slipping on first pull away and the tranny temp has not gone over even 175 so far and that's with ambient temps in ~95 degrees and stop n go traffic, same conditions that previously caused it to hit 190+.

So perhaps mine was under filled? Won't know really until I do the flush and see what I get on the drain/fill/test.

 

[AlisoBob]

I drained only 5 quarts from my tranny, filled with six ......so far, no shuddering, no gear slipping on first pull away and the tranny temp has not gone over even 175 so far

Which fluid did you use for the service ?

 

[Savinhillspyda]

Confirm you are performing the test drain plug with the trans temp at IIRC 185-203 Fahrenheit. I believe GM calls for that as that temp range triggers the TCM to release the reservoir perhaps and fill the tranny case, allowing an actual fill test. Service manual states that the reservoir is held back from release until certain parameters are met in the tranny case, one of which might be the temp range.

Also confirm you are performing the test with the engine running when you pull the plug. These are just to check nothing was missed or skipped by you.

I performed the drain and fill (but not the flush yet) on my 2018 HC last month, which was getting the shudder in low gears and lower end of speeds. My tranny temps were reaching 190-200 regularly after 30-45mins of driving and stop and go traffic. At these temps, the shuddering was always present (not to mention, when on first start and pull away from park, it would always slip at about 2-3 or 3-4 gear like clockwork on initial drive).

I drained only 5 quarts from my tranny, filled with six, ran the engine till that temp range (my HC still has the tranny temp on the dash display) and pulled the drain plug. I was only able to drain about 1/3 of a quart out. Garage is perfectly level (even checked with an actual level, as I change my oil as well for years here). Old tranny fluid was dark cherry/brown, but more brown than cherry. I have pics on my other phone, unfortunately.

Drove the car about 100 miles so far, not enough for me to do a flush yet (waiting to hit around 500 miles), so far, no shuddering, no gear slipping on first pull away and the tranny temp has not gone over even 175 so far and that's with ambient temps in ~95 degrees and stop n go traffic, same conditions that previously caused it to hit 190+.

So perhaps mine was under filled? Won't know really until I do the flush and see what I get on the drain/fill/test.

I def let the trans get to temp, Followed the how to instructions to a T! I thought a “Flush” was bad for the transmission?

 

[AlisoBob]

I thought a “Flush” was bad for the transmission?

I think so. I prefer to 'Double Dump" it.....

 

[26458]

Ouch! This stuff is expensive in the Great White North:

 

[Section9]

Which fluid did you use for the service ?

I used this one here Valvoline DEXRON VI/MERCON LV (ATF) Full Synthetic

It was $43 for a case of six at the time I bought. Only other cheaper one I found was a gallon contain of AC Delco, but not by much when segregated by quarts/ounces, at $28 a gallon. I checked the MSDS for each of them, even the approval letters and not really much difference between them. AC Delco had one additional additive for lubrication, but it was less than 0.5% per part, IIRC, that it seemed like a minuscule difference.

And it also turned out that a lot of these other brands are all from no more than a handful of the same manufacturers. Valvoline actually makes the AC Delco brand of tranny fluids for Dexron VI, during my research.

And BTW, I should clarify, I didn't mean a tranny flush, I meant the drain and dump. So I'll drain the tranny again and refill with another fresh batch.

 

[Section9]

Ouch! This stuff is expensive in the Great White North:

You should try searching by the case, it was the same here in the US, expensive per quart, cheaper by the case.

 

[26458]

You should try searching by the case, it was the same here in the US, expensive per quart, cheaper by the case.

Indeed. From the same screenshot above, Amazon.ca has a Case at $77.95 Cdn. That works-out to 12.99 per quart. Half the price of a Single quart. That is a bit better.

A case of Mobil 1 is about $143 Cdn on Amazon.ca.

I guess I'll go with the Valvoline from Amazon.

Thanks.

 

[ToddMeister]

Menards is selling the Valvoline Dex-IV full syn for about $5.00US per quart with 11% rebate currently.

 

[repairman54]

I've been using Amalie full synth. Dex VI from Amazon. 12 qt. case $74.02 Prime free shipping.
Nothing full synth. cheaper locally for me.

 

[vtmecheng]

Gotcha. Sounds like I can lower my DEFCON level a bit. Was probably 80° out and was going like 80mph for an hour or so...
Hottest it got was 220°. That sound ok? (Thanks for your write ups!)

220 seems high on an 80 degree day. I just ran some serious highway mountains on a 95 degree day at 75 mph and maxed out at 208 degF. Now I do have the tow package but even without it I would be a little uncomfortable with 220 for any amount of time. Just my opinion.

 

[Njtraverse]

Appreciate your input. I may start a thread asking folks to report their temps. I read somewhere the 9spds tend to run hot, and I do not have a tranny cooler, but regardless, I agree 220 seems high.

 

[AlisoBob]

#1 cause of overheating? Transmission is over full.

Checking the level is easy.......

On the freeway without towing anything, the T/C is locked up most all the time, which should keep the temps down.

 

[Njtraverse]

#1 cause of overheating? Transmission is over full.

Checking the level is easy.......

On the freeway without towing anything, the T/C is locked up most all the time, which should keep the temps down.

You've got me thinking that the tranny wasn't hot enough when I checked the fluid level; I'll revisit and post results. Hey, is there a transmission temp idiot light associated with this?