TRNW-2: Identifying 8L series units

[Steve Everett]

  Thanks Jim!

        Art looked up the part number I had and said it was for a truck
with a 5.3 ,  so its a 90, definitely not what the manager told me it came
out of, lol

   Steve

On Wed, Jul 9, 2025 at 11:16 AM Jim Mobley <hhcamobley at gmail.com> wrote:

> Steve,
> The ATRA 2021 Expo book has a lot of this information in form Steve
> Garrett.
> Also here is an article from Gears Magazine.
>
>
> https://gearsmagazine.com/magazine/8l90-changes-and-updates-they-are-not-created-equal/
>
> On Wed, Jul 9, 2025 at 7:53 AM Steve Everett via trnw2 <trnw2 at trnw.net>
> wrote:
>
>> Thanks Art ,
>>            this unit has a 24285391 part number on the tag, and has 15
>> pan bolts,  they ordered an 8L45 paper and rubber for it,  but the
>> tailhousing gasket is much larger on this unit than what came in the kit ?
>> according to that info it isn't a 90? maybe its a 50?  I may see if Reese
>> down at Aamco U can dig up anything on identifying these ?
>>
>>     I pulled the top plate on the valvebody and all the dampeners are
>> there and not a scratch on them anywhere, I'm pretty sure this valvebody
>> was never run in anything,  not sure why or how it ended up on what was
>> supposed to be a stock unit ?
>>
>>    Steve
>>
>> On Wed, Jul 9, 2025 at 10:40 AM Art Landeck <artrans at optimum.net> wrote:
>>
>>> Here is the answer AI gives
>>> [image: bGVnYWN5_bd236d88-3f19-458b-a86a-3ccb9883f862.png]
>>>
>>> Identifying GM 8L Transmissions | Shared Grok Conversation
>>> <https://grok.com/share/bGVnYWN5_bd236d88-3f19-458b-a86a-3ccb9883f862>
>>> grok.com
>>> <https://grok.com/share/bGVnYWN5_bd236d88-3f19-458b-a86a-3ccb9883f862>
>>> <https://grok.com/share/bGVnYWN5_bd236d88-3f19-458b-a86a-3ccb9883f862>
>>>
>>>
>>>
>>> Sent from my iPhone
>>>
>>> On Jul 9, 2025, at 10:35 AM, Steve Everett via trnw2 <trnw2 at trnw.net>
>>> wrote:
>>>
>>> 
>>>    I can find nothing in any of the tech I have that helps to identify a
>>> unit,  the tI'ag on the trans has 0XNL in big letters ,  assuming it works
>>> like most GM units it is apparently a 2020 unit?  which would be correct in
>>> a 2021 vehicle,  I'm sure the XNL would tell me something? I just can't
>>> find anything that tells me what ?
>>>
>>>    I've agreed to work part time , 3 days a week at an Aamco here in the
>>> Metro area,  and this is a stock unit they somehow ended up with,  another
>>> builder built it and had left two thrust bearings out of it, and had at
>>> least one of the snap rings indexed incorrectly, but when it get it all
>>> back together I need to make note of what vehicles it will fit in ?   it
>>> has a brand new GM valvebody on it that they don't remember buying ?
>>>
>>>    Steve
>>>
>>> On Wed, Jul 9, 2025 at 9:56 AM pat schulte <zzyzxpat at gmail.com> wrote:
>>>
>>>> I know that the 8L45/50s I have seen do not use a dipstick and the
>>>> fluid check is in the pan, but I think the very late 90s have gone that way
>>>> as well. Not a stupid question, I have wondered this myself.
>>>>
>>>> On Wed, Jul 9, 2025 at 6:32 AM Steve Everett via trnw2 <trnw2 at trnw.net>
>>>> wrote:
>>>>
>>>>> This is probably a stupid question,  does anyone know a way to tell if
>>>>> an 8L is a 45,50 , or 90 by looking at the outside tag ?   similar to how
>>>>> we identify the 6L's ?  I'm going through a unit someone built to make sure
>>>>> its correct, and was told it came from a 2021 V6 camaro, which according to
>>>>> what I looked up should be a 8L45,  but its not
>>>>>
>>>>>    I've built 6 or 7 of these, but haven't figured out how to tell
>>>>> them apart yet
>>>>>
>>>>>    Steve
>>>>> This message was sent from the TRNW Technical Discussion Forum
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>>>>> TRNW Inc., 2825 Walnut Terrace, Modesto, CA 95355
>>>>
>>>>
>>>>
>>>> --
>>>> Pat Schulte
>>>> AAMCO Transmissions
>>>> Temecula, Ca.
>>>>
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>
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