[radz28]

Along the lines of the GM transmission engineers:

Some of the videos out there have commentary by the lead engineer of a company that sells the remedy to these issues. That company has a video showing the installation of their products for these transmissions. That video, also, details where the THERMOSTAT is for some these transmissions. As I said before (unlike your statements in other posts), I'd make sure to confirm where your thermostat is before installing any by-pass (as photos show in my thread of me replacing said components). The by-pass won't do much if the thermostat is in the valve body, like my '20 (I don't know when the change was - all I know is I, also, inspected [by feel] for a by-pass at the fluid inlet/outlet manifold on the side of the transmission and there were NO orifices for another thermostat). Telling people to slap in the by-pass without context could be a waste of money, or worse, for example. AND - it's out there that there are differing temperatures to check fill for differing years and such. That's another thing to consider. TRUCKS seem to have the by-pass there, but stating it's there, when you don't know, and don't know there are differing temperatures to check fluid level, is bad advice. That isn't the customer's fault. It did sound like this was a problem until they paid for the service.


@ 16:39



EVERYONE SHOULD DO THEIR OWN RESEARCH and confirm what they're paying for. This thread is GREAT for showing exactly what's going on, what to do with what, and seems to be logical at every step. AWESOME, and thanks for sharing.

[ZLRob]

Originally Posted by Patriot Motorsports USA

Everything GM does is for a reason... like telling you 0W/20 oil is great, then 5w/30 then 0w/40 after the class-action suits keep coming. Then they use the standpipe to reduce lawsuits by Techs for getting burned by using a plug because of the proximity to the exhaust or the dangers of igniting ATF on a hot exhaust. It makes the process, sure it does... if you have the pump, adapters and all the tools to make it work from a Dealership's perspective.

Copied Directly from GM TSB notifications to Dealers

General Motors (GM) has issued numerous Service Bulletins to address safety risks and technical errors associated with the "bottom-fill" (standpipe) method used on many modern transmissions.

The Standpipe Fill Safety Concerns
The "standpipe" or "bottom-fill" method—used on transmissions like the 8L45, 8L90, 10L80, and 10L90—replaces the traditional dipstick with a tube in the bottom pan. This procedure presents specific safety risks:
Burn Hazard: Technicians must check the fluid while the engine is running and the fluid is at operating temperature (typically between 95°F and 113°F for 8-speeds, or up to 176°F for 10-speeds).

Proximity to Heat: Checking the level requires being under the vehicle near hot exhaust components while hot fluid may "drizzle" or "drip" out of the check plug.

Overfill Fire Risk: GM warned in Service Bulletin 15667 that over-filled transmissions can discharge fluid out of the vent tube, potentially causing a fire and serious bodily injury.

Major GM Transmission Litigation
Regional technician-specific lawsuits for burns:
GM is currently facing massive consumer class-action lawsuits regarding these same transmissions:

End of GM TSB

Not every enthusiast has a shop with a lift, Mity-Vac hooked to an air compressor nor the capability to build the special tools to get the plug out when the trans is being operated on a running car. The REASON I use the side method is because I can insert the Mity-Vac straw into the case, sucking down several quarts of fluid to do my "Gender-Neutral-Shift-Juice" by removing the pan to check it for any wear. I also can fill it while having the standpipe plug open to see it dribbles at the exact time the fluid trickles out the side. I have never said that I am NOT using the standpipe, but I am not using it as the fill, nor extraction point either because I have figured a simpler way most can relate to without buying another full kit of tools.

But if you want to buy the kit to do the fill with the Standpipe, here it is on Amazon.

The problem with these kits is that when you are filling with the car running... you have to guess at the overfill, then waste fluid that costs over $16/quart to let it run down your arm at 150º while trying to get the stupid fitting off the pan to then let it level off. OR... you can do it my way, fill it from the side plug and know if all things like the moon & stars are aligned with temps, leveled car on the lift and birds singing, the ATF level will be just right.

14,630 track miles, 37K miles total on the OEM A10 with zero issues. YUP... seems to be working just fine. Add to that history, two-dozen or so other A10s filled by me with zero history of shifting issues, except one that had an "extra quart" at 50º over the highest operating temp.

Unfortunately/ fortunately, GM designed our transmission the way they did. It's a catch 22 because by eliminating a dipstick function from our system it eliminates the possibility of moisture entry from the dipstick tube area. It's a good thing but a bad thing all at the same time because it makes it that much harder to check fluid levels.


That being said, with how sensitive these systems are to being over/ underfilled it's almost a good thing these have a "fill to spill" type of set up because it allows you to maintain a consistency in level inspection as long as you follow the method properly every single time. Let's say your system takes 5 quarts at 203-212* F. As long as you perform the procedure the same way you will get consistent results every single time and you will know without a shadow of a doubt that the fluid level is correct based on fluid expansion of that temperature range.


The way you have been doing it Dave is technically not approved by the book (I am not one to follow book procedures at this stage in my life based on the major shortcomings I have consistently found that they have, however, this situation I make an exception for based on design of the transmission as a whole). If it works for you then that's awesome, but in a full factory configuration you have to remove the pan and filter to do a drain and fill, then after that is done, you remove the side plug on the back of the case of the drivers side which takes a stubby M10 hex key to access and then you fill from there. After you fill up based on whatever you pulled out for the most part then you bring it up to whatever the appropriate temp is for your model year is then you remove the plug for the standpipe and let out however much it may be overfilled with if it is.


I experienced slippage and generally bad engagement just by being overfilled with as little as .3 quarts. Even as I write it right now it's coming off as outlandishly silly to me, but here I am. I don't remember if I wrote that here or in the ultimate pan thread, but regardless, it's a testament to how much of the ragged edge of tuning and engineering GM and Ford did at the time of designing the A10's to get these things to perform properly.

[Patriot Motorsports USA]

Originally Posted by ZLRob

Unfortunately/ fortunately, GM designed our transmission the way they did. It's a catch 22 because by eliminating a dipstick function from our system it eliminates the possibility of moisture entry from the dipstick tube area. It's a good thing but a bad thing all at the same time because it makes it that much harder to check fluid levels.


That being said, with how sensitive these systems are to being over/ underfilled it's almost a good thing these have a "fill to spill" type of set up because it allows you to maintain a consistency in level inspection as long as you follow the method properly every single time. Let's say your system takes 5 quarts at 203-212* F. As long as you perform the procedure the same way you will get consistent results every single time and you will know without a shadow of a doubt that the fluid level is correct based on fluid expansion of that temperature range.


The way you have been doing it Dave is technically not approved by the book (I am not one to follow book procedures at this stage in my life based on the major shortcomings I have consistently found that they have, however, this situation I make an exception for based on design of the transmission as a whole). If it works for you then that's awesome, but in a full factory configuration you have to remove the pan and filter to do a drain and fill, then after that is done, you remove the side plug on the back of the case of the drivers side which takes a stubby M10 hex key to access and then you fill from there. After you fill up based on whatever you pulled out for the most part then you bring it up to whatever the appropriate temp is for your model year is then you remove the plug for the standpipe and let out however much it may be overfilled with if it is.

.

Please see my text that you quoted. I do remove the standpipe to check fluid and while the car is running, that is literally the method I use to fill the transmission, but I am filling and draining from the plug BEFORE removing the pan. My ONLY check in this thread was stating prolifically that the temperature shared by Toto was incorrect and that due to fluid expansion at such a temperature variance above what is GM specification for our cars, would produce the exact quart if not more due to the thermal expansion of checking it using such a specification. That's it. Once again, the differences between all the pans, vehicles and such are why there is a difference in the standpipe height, but I can unequivocally share the pan that comes with the street-rod 10L90E transmission is identical to the ZLE with the only exception being the Tahoe PPV slip yoke tailshaft. We just had one here for a customer's build who is going with a carbon driveshaft in a 2017 CTSV 8spd to A10 swap.

Here is the bypass we use without a thermostat since the 2020+ ZLE A10 with an internal thermostat begins to open at 140º.

https://www.youtube.com/shorts/hp-CbrqA4OU

[ZLRob]

Originally Posted by Patriot Motorsports USA

Please see my text that you quoted. I do remove the standpipe to check fluid and while the car is running, that is literally the method I use to fill the transmission, but I am filling and draining from the plug BEFORE removing the pan. My ONLY check in this thread was stating prolifically that the temperature shared by Toto was incorrect and that due to fluid expansion at such a temperature variance above what is GM specification for our cars, would produce the exact quart if not more due to the thermal expansion of checking it using such a specification. That's it. Once again, the differences between all the pans, vehicles and such are why there is a difference in the standpipe height, but I can unequivocally share the pan that comes with the street-rod 10L90E transmission is identical to the ZLE with the only exception being the Tahoe PPV slip yoke tailshaft. We just had one here for a customer's build who is going with a carbon driveshaft in a 2017 CTSV 8spd to A10 swap.

Here is the bypass we use without a thermostat since the 2020+ ZLE A10 with an internal thermostat begins to open at 140º.

https://www.youtube.com/shorts/hp-CbrqA4OU

That's my fault. I skimmed like hell and when I combed over it quickly I read it as in you saying you didn't use the standpipe and just checked level from the side plug height level.

[Patriot Motorsports USA]

Originally Posted by ZLRob

That's my fault. I skimmed like hell and when I combed over it quickly I read it as in you saying you didn't use the standpipe and just checked level from the side plug height level.

LOL!! I do the same thing with long posts... I tend to go into "Building the Clock, to tell people what Time it is!"

I hope you see what my point is though... if you are filling the transmission USING the standpipe without removing the plug, you cannot see when you have overfilled or begin wasting really expensive Amsoil ATF. By warming the transmission and filling from the plug, the standpipe will be the tattle-tail as the fluid is thermally expanding to be the "check" for the proper capacity. Far less waste and mess.

[radz28]

ZLRob - if it's okay with you, I would like to share information a valuable Member's information that he shared when he had to refill the fluid. While not quite on topic, I feel like it's good information to think about. I'm going to add it, but if you feel it's not appropriate, I can pull it. I feel like I needed to do something constructive and helpful, and can find more information if anyone would like some. It's not special, nor new, but sometimes having it in one spot can be helpful to someone I suppose.

Here's what Roddrz shared in his experience and research when he refilled his tranny after the valve body upgrades:

"You'll need at least 14 quarts according to AMSOIL, if you have a transmission cooler.
I ordered 14 from AMSOIL and delivery is normally the next day, but I order a couple extra in case I kick one over or I don't want to run short.
Note: I run a V6 10L60 with 11.5 quarts that uses less fluid than the 10L80.

If you do run short, Mercon ULV has a higher temp rating than Dexron ULV; however, AMSOIL's specifications exceeds both Mercon and Dexron.

If I recall, you are installing the NextGen Drivetrain Valve Body Upgrade kit.

When installing, remove the transmission thermostat for better cooling but now you can also do a full flush of all 14 quarts without having to bring the transmission up to a certain fluid temperature.

Besides I can never get the tranny temp much past 165 Fahrenheit with a cooler that is disconnected from the engine's radiator coolant heater.

When you drop the pan, why not install a drain plug?
I recommend a good plug with gaskets and it does not leak.
(Superior Transmission Parts)

When you drop the Valve Body, another 4 quarts will slowly drip out into a catch basin. The transmission pan holds 4 quarts, 4 more quarts are in the torque converter and 1 quart in the cooler and lines.

After everything is reassembled:
Prime the pan with 5 quarts of fluid
Disconnect the output line from your cooler into a large drain pan
(To find the output line, before changing fluid, run the car to find the cold return)
Then start your car
Shift it into neutral
Start pumping the rest of the fluid into the refill hole using a GM adaptor tool and an electric pump
(CTA Tools 7431 ATF Filler Adapter - M6x1.0)
On average the dirty fluid pumping out from the tranny, changes color to clean just as I run out of fluid pumping in
GM recommends to have no fluid drip from their drain straw
So this is where the drain plug facilitates draining some fluid, if required
I've provided the calculation for expansion and the result is very little fluid approximately, 1/2 quart
Coefficient of thermal expansion for oils and transmission fluids is around 0.0007 per degree C (0.07%/C).
https://bobistheoilguy.com/forums/th...h-heat.316726/

Summer time temperature change might be ambient air temperature 68F (20C), at start up, to around 180F(82C) at operating temperature. Or, around 62C.

Therefore, during the summertime, the fluid could be expected to expand 0.0007 x 62C = 0.0434 (4.3%).

10.8 L expands 464 mL
Therefore fill to the fill tube over flows, then remove 400 ml from the pan (typo: not the cooler)."

https://www.camaro6.com/forums/showp...&postcount=135

[Patriot Motorsports USA]

RODDRZ definitely went above and beyond on the A10 disassembly. Did he ever get the Valve Body swap working..? I had reached out to Nate at NGD last year and offered to send them mine to do the upgrades, even offered to send my car there as I have a friend who lives nearby their shop. Never got a reply.

[ZLRob]

Originally Posted by Patriot Motorsports USA

LOL!! I do the same thing with long posts... I tend to go into "Building the Clock, to tell people what Time it is!"

I hope you see what my point is though... if you are filling the transmission USING the standpipe without removing the plug, you cannot see when you have overfilled or begin wasting really expensive Amsoil ATF. By warming the transmission and filling from the plug, the standpipe will be the tattle-tail as the fluid is thermally expanding to be the "check" for the proper capacity. Far less waste and mess.

When it comes to ATF, especially this stuff, I have just come to accept that there will always be some waste that comes with it. Basically making this stuff the equivalent to a consumable item. I usually just fill to a certain volume now and then just drive and empty from standpipe as needed once I hit the right temp range. Now that I have the quick fill port affixed to the pan, I really don't have to wait to do anything. Life is so much easier with this set up these days.

Originally Posted by radz28

ZLRob - if it's okay with you, I would like to share information a valuable Member's information that he shared when he had to refill the fluid. While not quite on topic, I feel like it's good information to think about. I'm going to add it, but if you feel it's not appropriate, I can pull it. I feel like I needed to do something constructive and helpful, and can find more information if anyone would like some. It's not special, nor new, but sometimes having it in one spot can be helpful to someone I suppose.

Here's what Roddrz shared in his experience and research when he refilled his tranny after the valve body upgrades:

"You'll need at least 14 quarts according to AMSOIL, if you have a transmission cooler.
I ordered 14 from AMSOIL and delivery is normally the next day, but I order a couple extra in case I kick one over or I don't want to run short.
Note: I run a V6 10L60 with 11.5 quarts that uses less fluid than the 10L80.

If you do run short, Mercon ULV has a higher temp rating than Dexron ULV; however, AMSOIL's specifications exceeds both Mercon and Dexron.

If I recall, you are installing the NextGen Drivetrain Valve Body Upgrade kit.

When installing, remove the transmission thermostat for better cooling but now you can also do a full flush of all 14 quarts without having to bring the transmission up to a certain fluid temperature.

Besides I can never get the tranny temp much past 165 Fahrenheit with a cooler that is disconnected from the engine's radiator coolant heater.

When you drop the pan, why not install a drain plug?
I recommend a good plug with gaskets and it does not leak.
(Superior Transmission Parts)

When you drop the Valve Body, another 4 quarts will slowly drip out into a catch basin. The transmission pan holds 4 quarts, 4 more quarts are in the torque converter and 1 quart in the cooler and lines.

After everything is reassembled:
Prime the pan with 5 quarts of fluid
Disconnect the output line from your cooler into a large drain pan
(To find the output line, before changing fluid, run the car to find the cold return)
Then start your car
Shift it into neutral
Start pumping the rest of the fluid into the refill hole using a GM adaptor tool and an electric pump
(CTA Tools 7431 ATF Filler Adapter - M6x1.0)
On average the dirty fluid pumping out from the tranny, changes color to clean just as I run out of fluid pumping in
GM recommends to have no fluid drip from their drain straw
So this is where the drain plug facilitates draining some fluid, if required
I've provided the calculation for expansion and the result is very little fluid approximately, 1/2 quart
Coefficient of thermal expansion for oils and transmission fluids is around 0.0007 per degree C (0.07%/C).
https://bobistheoilguy.com/forums/th...h-heat.316726/

Summer time temperature change might be ambient air temperature 68F (20C), at start up, to around 180F(82C) at operating temperature. Or, around 62C.

Therefore, during the summertime, the fluid could be expected to expand 0.0007 x 62C = 0.0434 (4.3%).

10.8 L expands 464 mL
Therefore fill to the fill tube over flows, then remove 400 ml from the pan (typo: not the cooler)."

https://www.camaro6.com/forums/showp...&postcount=135

This is great data. I think I read this exact post at one point before I did my pan replacement. Roddrz is the man for doing the work that he did on these transmissions at the time.

Originally Posted by Patriot Motorsports USA

RODDRZ definitely went above and beyond on the A10 disassembly. Did he ever get the Valve Body swap working..? I had reached out to Nate at NGD last year and offered to send them mine to do the upgrades, even offered to send my car there as I have a friend who lives nearby their shop. Never got a reply.

That reminds me, I gotta call them actually and give them the good news about the aluminum replacement pan working on Gen 1 A10's. Thanks for the reminder man! Lol.

[radz28]

Roddrz method makes the most sense to me, because you can calculate how much to drain out of the PAN (not the standpipe) by calculating the coefficients based off temperatures. Once the rates of expansion are calculated, you can remove what's excess by correcting by temperature so you don't have to get past the thermostat opening. THAT'S AS LONG AS THE THERMOSTAT'S REMOVED, so that's why I keep emphasizing that so much, because if it's not, you're not going to have purged all the air from the system. AND - because ZLEs have shorter pans to hold less fluid to keep from cavitating, one will want to make sure they're not over-filling, as stated earlier. After enough driving and shifting through the gears, this method makes the most sense. I only had to buy a pump and that standpipe fitting and I can reuse those for the future.

I can affirm NGD has a correct separator plate for at least my car that precisely matches the OEM one that came out. I don't know if it will work for all Gen I 10L90s but I'm sure it will for all Gen IIs. I can't confirm that, though, but have matched it with mine, as I said, and it matches perfectly. I would recommend anyone confirm this during their install, just like I did. I know NGD will want to provide anyone with the correct one, so as they start to serve all versions out there, their going to want to make sure they send you the correct version for your application.

The one that I received, originally, came with 3-missing orifices, and it took them weeks (as Tyler hoped it would) to revise a new one that matched what I had. I didn't even have to send mine in. I think they've, primarily, been working with trucks, so I know mine was a new version they encountered. They countered the difference with a brand new version, and same high quality anodized product as they produced before. These guys are top-notch. Mine's been installed for a couple months, but weather has kept me from driving, but I'm looking to put some miles on him soon, and will report back in my thread on the install.

[RobZL1]

I mean, the solution here is obviously a man pedal.
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Just kidding of course.

[Patriot Motorsports USA]

Originally Posted by radz28

I can affirm NGD has a correct separator plate for at least my car that precisely matches the OEM one that came out.

These guys are top-notch.

Indeed they are and thanks for sorting out the issues. I will give them a call next week when I get caught up with cars in the shop and orders. I definitely cannot wait to see what it does for the drivability around town and on the track!

[JSH]

Originally Posted by ZLRob

This has been a semi intermittent issue. .. so I don't think this issue is new at all.

I keep seeing activity on your thread here, and I'm still puzzled about why your clutches are slipping, particularly since your HP isn't asking that much of them. I've got 200 more hp, and mine feels new despite 17k hard miles. All I've done is change the fluid and filter once, maybe twice. No way am I as diligent as you are.

Has there been some unusual event along the way that could have hurt it?

[ZLRob]

Originally Posted by JSH

I keep seeing activity on your thread here, and I'm still puzzled about why your clutches are slipping, particularly since your HP isn't asking that much of them. I've got 200 more hp, and mine feels new despite 17k hard miles. All I've done is change the fluid and filter once, maybe twice. No way am I as diligent as you are.

Has there been some unusual event along the way that could have hurt it?

The trans was serviced at 9K miles in 2019, I believe, when I didn't own it. They did a full flush (with GM ULV at the time) and wound up leaving .3 quarts excess in it. It doesn't sound like much but that .3 quarts was enough to absolutely piss the transmission off and throw off its shifting characteristics. After I brought everything up to proper temp and drained out the excess fluid on it it was like a full on attitude adjustment because all of the weird issues finally went away.