Just Fishing's 09 Tahoe Build thread

[Just Fishing]

One more upgrade would be a proactive replacement of the 4-5-6 clutch hub and shaft.
Apparently, it's a known weak point.
shafts break, and the welds fail.
Lots of different updates per sonnax for the OEM to fix it.
they offer one, but it's $$$$$$

They also mention that the oem unit was only rated for 400hp.
I'm a little worried about "Shock" due to aggressive shift tuning.

and I'm not sure if I'll exceed the rating or not, but I think there is a very good chance of it...

I'm debating about replacing it with an OEM unit proactively.
Assuming I can find one in stock.

 

[Just Fishing]

Durabond bushings are good. Make sure you have the correct driver tools or they mushroom super easy

Thanks, i just checked my current bushing drivers and confirmed only a few of them actually fit bushings in this transmission.
I'll get another set ordered as soon as my amazon pump rotor arrives and is returned that is...

 

[pwtr02ss]

Do all the upgrades you can while it's out. It's always "damn, I should've just done that while I had it out" if it breaks.

 

[Just Fishing]

Do all the upgrades you can while it's out. It's always "damn, I should've just done that while I had it out" if it breaks.

Yeah, that's always the problem...
Ugg.

parts prices for the 6l80 makes my wallet hurt.

 

[pwtr02ss]

Yeah, that's always the problem...
Ugg.

parts prices for the 6l80 makes my wallet hurt.

Just price out buying one with those upgrades that someone else did. It makes it easier

 

[Just Fishing]

Just price out buying one with those upgrades that someone else did. It makes it easier

If not for the engine being way over budget, i would do all upgrades.

But for this, i can't have it leave me stranded in the desert.

More reading to do, i don't see much mention of those shafts breaking unless we are talking boosted.


And i have a few more tools on order.
Nice speedy amazon refund went towards some drum tools, and a nicer bushing driver kit.

And now i have a drum to test on since it's getting replaced.

 

[pwtr02ss]

If not for the engine being way over budget, i would do all upgrades.

But for this, i can't have it leave me stranded in the desert.

More reading to do, i don't see much mention of those shafts breaking unless we are talking boosted.


And i have a few more tools on order.
Nice speedy amazon refund went towards some drum tools, and a nicer bushing driver kit.

And now i have a drum to test on since it's getting replaced.

Best I remember, the hard parts are pretty stout. I do remember reading about the drum issues that you mentioned. You already have all the pump and valve body upgrades, along with torque converter. I'd only replace the bushings that show wear. Leave the rest. I like the Teflon coated bushings as well. Be warned. They don't look the best after they've been beating around in the pack, just file the little places you see, very lightly. Not on the Teflon surface though. Just the places in the brass. I've never had a problem with that method.

 

[Just Fishing]

Most of what I have in that transmission looks fantastic.
I have yet to pull the rear support stuff, but the tool for it just arrived today.

It's going to be exciting soon!



I also got the shipping notice for my rods last week, but I don't see any action in the tracking information...

So, it looks like I might be doing the transmission before I complete the engine.


Oh well, should be easier to install the transmission and t-case as one unit.
Lifting in and then rolling back into place, with the t-case above the one crossmember that can't be removed.

 

[Just Fishing]

Best I remember, the hard parts are pretty stout. I do remember reading about the drum issues that you mentioned. You already have all the pump and valve body upgrades, along with torque converter. I'd only replace the bushings that show wear. Leave the rest. I like the Teflon coated bushings as well. Be warned. They don't look the best after they've been beating around in the pack, just file the little places you see, very lightly. Not on the Teflon surface though. Just the places in the brass. I've never had a problem with that method.

Part of my plan is to check the fitment of the new bushings vs the ones installed.
Then I believe that should help make my decision related to how worn they are.

There are ones like on the input shaft, they recommend replacing each time.
tiny little guy.

I also want to do the output shaft bushing.

When I pulled this thing, I noticed how much end play I have.
I swear I was like 1/8th of an inch.
Apparently, the spec is something around 20 thousands.

So, I'm expecting some wear to be found.
then the fun of the shimming...
Not much information about that, but there are kits that are sort of hard to find.



But in the end, this transmission worked fine.
This is mostly to ensure that metal didn't make its way from the pump into the internals.

 

[pwtr02ss]

Part of my plan is to check the fitment of the new bushings vs the ones installed.
Then I believe that should help make my decision related to how worn they are.

There are ones like on the input shaft, they recommend replacing each time.
tiny little guy.

I also want to do the output shaft bushing.

When I pulled this thing, I noticed how much end play I have.
I swear I was like 1/8th of an inch.
Apparently, the spec is something around 20 thousands.

So, I'm expecting some wear to be found.
then the fun of the shimming...
Not much information about that, but there are kits that are sort of hard to find.



But in the end, this transmission worked fine.
This is mostly to ensure that metal didn't make its way from the pump into the internals.

On the end play stuff, I believe they make thicker/thinner washers. I check every 4L60 that we've built but they've all went right back together and been within spec. They have all been at the very top of the spec but I haven't had issues with them. I glad you're tearing into one. When the day comes, I'll have some questions for you!