Advanced adapter to 6l90 questions

[georgiacruiser87]

Ok guys I’ve got a 6l90 4wd from a 2012 suburban 2500. I’m getting ready to start moving the transfer case over with the advanced adapters kit and I’m coming across a few questions already. I’m sure I’ll have a lot more so, but first:

The amount of output shaft after removing the tail housing is confusing me. I’m at 3.75” and the directions say they need 4” of stick out. I’m assuming advanced adaptors most likely measured the entire output shaft and not just what’s sticking out. The directions also say there needs to be 1.55” of splines left so should I just mic the 1.55 and cut the remainder off?

Also, does anyone have any pictures or better instructions than what I’m finding online. These 3 pages from advanced adapters is lacking a lot for my 4th grade reading level mind. I’d rather do it myself, but man this is sort of a daunting task. Thanks in advance.

 

[BurntToast]

I think I dry fit mine after test fitting to make sure it would all bolt together.

This is a kinda crap pic of how mine looked, but it was 2WD. I think the 4WD transmission shafts are already short?

Build Post in thread 'BurntToast's FJ62 Build "Hoss"'

Dec 21, 2023

Hoping to get some feedback from smart people here. Called AA to ask if their intermediate bearing (between adapter and tcase) can run dry. They said yes. Seems odd no?

if done per their instructions the 2wd 6l80 gets its rear holes plugged and a seal around the shaft like the 4wd version. So no trans fluid in the adapter. There is also a double lip seal after the adapter and bearing that seals the Tcase. So I. Theory no fluid of any kind.

Do pack it with grease??

• BurntToast

 

[georgiacruiser87]

I think I dry fit mine after test fitting to make sure it would all bolt together.

This is a kinda crap pic of how mine looked, but it was 2WD. I think the 4WD transmission shafts are already short?

Build Post in thread 'BurntToast's FJ62 Build "Hoss"'

Dec 21, 2023

Hoping to get some feedback from smart people here. Called AA to ask if their intermediate bearing (between adapter and tcase) can run dry. They said yes. Seems odd no?

if done per their instructions the 2wd 6l80 gets its rear holes plugged and a seal around the shaft like the 4wd version. So no trans fluid in the adapter. There is also a double lip seal after the adapter and bearing that seals the Tcase. So I. Theory no fluid of any kind.

Do pack it with grease??

• BurntToast

I went through your build thread this morning. I’m going to do the same thing. No cutting and just start and make sure everything works. If or once I run into an issue I will take it all back apart and it only cost me time.

Now I’ve got to find a closed bearing. They sent me the same one they sent you years back.

 

[EWheeler]

Did you call AA and confirm your kit will work with the 4wd version of the trans?

The instruction sheet in Burnt Toast's photos is for the 2wd transmission kit, PN 50-9612.

6L80 TO TOYOTA L/C 19 SPLINE

buy 6L80 TO TOYOTA L/C 19 SPLINE online

www.advanceadapters.com

There is PN 50-9615 which is for the 4wd transmission.

6L90 TO TOYOTA L/C 19 SPLINE

buy 6L90 TO TOYOTA L/C 19 SPLINE online

www.advanceadapters.com

I assume because they are specific part numbers there is a difference between the kit, so you probably want to confirm what that difference is, and what actual parts you have.

 

[georgiacruiser87]

Did you call AA and confirm your kit will work with the 4wd version of the trans?

The instruction sheet in Burnt Toast's photos is for the 2wd transmission kit, PN 50-9612.

6L80 TO TOYOTA L/C 19 SPLINE

buy 6L80 TO TOYOTA L/C 19 SPLINE online

www.advanceadapters.com

There is PN 50-9615 which is for the 4wd transmission.

6L90 TO TOYOTA L/C 19 SPLINE

buy 6L90 TO TOYOTA L/C 19 SPLINE online

www.advanceadapters.com

I assume because they are specific part numbers there is a difference between the kit, so you probably want to confirm what that difference is, and what actual parts you have.

I have the kit for the 4wd
My confusion lies with the 4wd 6l90 came with 2 separate output shafts one longer than the other.
I have the shorter one. I’m just going to go for it this weekend and see what happens. I can always tear it back down if it doesn’t look right.

 

[georgiacruiser87]

I just got off the phone with advanced adaptors and their technician said the open bearing was correct. ‍♂ I wonder how long it will last.

 

[BurntToast]

I just got off the phone with advanced adaptors and their technician said the open bearing was correct. ‍♂ I wonder how long it will last.

Read my thread, every professional cruiser shop and engineer disagree with AA. I would just order the part number I did and wait.

Edit: lol AA even have the sealed bearing in their product photo on the webpage