bortous

Hi everyone and welcome to this thread.
Hope you are all having a good day and are happy with your lives.

I have an 4L65E transmission that was fully rebuilt around 7 years ago.

It's still running strong however I have not abused it.
The original power rating of the built transmission was 600hp for maximum reliability but it can hold to 750hp or so before breakages become likely.
I have an LS 408 stroker engine making 650-700hp at the moment and I really want to put a blower on which should net me around 1000hp.
I am aware of the limitations of this transmission and I certainly do not want to push it.
Doing a 4L80 E conversion is out of the question because of the cost involved.
The transmission is in a vehicle with the 2004-2006 Pontiac GTO chassis.

I have noticed from Sonnex, that they have some new parts out for these transmissions:
Sonnax 2nd Gear Super Hold Servo Kit 77911-03K
Sonnax Heavy Duty Sun Shell Kit 77749-02K
Sonnax 6 Pinion Front-Input Planetary 77284-K

Without those three optional upgrades a stage 4 master rebuild kit can support up to 750hp reliably but they recommend for strip vehicles to keep the power to 700hp.

Does anyone know with those optional upgrades if this transmission could hold 1000hp or more than 750hp reliably?

MaroonMonsterLS1

what do you mean "stage 4 rebuild kit"...who do you plan to buy through?

1. the super hold servo is a nice piece. Use it in conjunction with a NEW reverse input drum, and a Carbon (NOT KEVLAR) extra wide band.
2. The sun shell kit is great. Really helps with thrust bearing issues.
3. Do no waste your time or money with this part

Who do you keep talking about "they" recommend. What company are you dealing with.

And no...those parts are not going to be the weak link at your power level.

bortous

Trutech transmissions is the place via eBay.
It also comes ray bestos blue plate frictions.

So is there a way to make this transmission cope with more power reliably?

MaroonMonsterLS1

holy crap. 1600 bucks for $600 worth of parts.

1. Complete Raybestos Blue Plate Friction Kit: Meh. Nothing special but it's a nice friction
2. Complete set steels with 3-4 Kolene steels: Again...meh ALSO it doesn't say how many frictions...that's concerning
3. Complete gasket and seal kit: $20 whooptie doo. Nothing special
4. Wide Raybestos Pro Series Band:Good
5. ACdelco 3-4 Apply and Backing plates for proper 3-4 clearance: Likely a .223 and .157 set with .093 snap ring. Again...nothing special
6. New ACdelco reverse input drum: This is very good...but you don't need the new apply piston they show in the kit. Use the one from your core
7. "Beast" sun shell: Sonnax shell is better...simply for the thrust control
8. ACdelco 5 pinion rear planetary gear: If you want to waste a bunch of money...get 5 pinions haha
9. ACdelco 5 pinion front planetary kit: Same comment as #8
10. Sonnax input drum reinforcement kit: You'll hear different sides to this story. In my opinion, it doesn't fix any problems. It just moves the problem to a different location.
11. Trutech Performance Shift Improvement Module: Sounds like a custom shift kit...I doubt they have anything special in here
12. Raybestos heavy duty 29 element forward sprag: Good...make sure you prep the race properly
13. Complete bushing kit with Teflon front pump bushing: 60e isn't hard on bushings as much as other units. Replace pump bushing, double up sun gear bushing. The rest likely won't need much attention...but inspect them all
14. Complete thrust washer kit: your 65 will likely be almost all roller bearings. So you won't hardly use any of this
15. ACdelco 3rd accumulator and 3-4 exhaust check valves for hydraulic integrity: The superior k0136 is the best option for the 3rd accum checkball
16. 3 input drum bonded steel clutch pistons: Standard with any rebuild
17. Sonnax replacement load release springs:Don't waste your time
18. Quality OEM filter: who cares

So...it sounds like it is a basic rebuild with 5 pinion planets and a new reverse drum...

Go read KFXguy's thread...lots of useful info there and I have tried to share some tips and tricks in his thread.
I can be pretty confident in saying that if you just do a standard rebuild with the kit you have mentioned...you're going to be pretty dissatisfied. and Likely smoke a trans

bortous

So what do you recommend is the best approach?

MaroonMonsterLS1

I told you what I think the best approach is...go read kfxguy's thread
also read cayenne ws6 thread

both have probably 100+ posts in the thread...so get comfy and start making notes

if you read both of those end to end and still have questions, then post back in here and people can help answer

bortous

I contacted KFXguy and we are communicating.
He confirmed with me there is no way this transmission will hold 1000hp.
You might be able get 5 or 6 track runs before it starts to break.
But damn, I wish someone would come out with something that will let these transmissions handle in excess of 1000hp reliably.
That would be so good.

MaroonMonsterLS1

performabuilt claims they can make some magic happen.
they will warranty 1000 horse.

I would never actually try that...but you go to town haha

750 can and has been done reliably...but not cheaply

Since it is a GTO...I know there are other transmissions that will fit.
About the only cars youre really stuck without a swap are c5 and c6 corvettes...and even then you can get a glide if youre willing to drop the cash

bortous

It cost me $3000 USD to rebuild mine but I wanted maximum specification.
Worked out good.
I will check out that performabuilt place.
There was a guy here though that got his 4L65E to break at 850hp.
If I had the newer HSV which comes with the 6L90E and rebuilt it this would handle 1200hp no problem.
Maybe one day....

performabuilt

iTrader: (25)

We indeed do have 4L6X E units presently running in excess of 1000 RWHP long term meaning several years. And if you go to our Facebook you can find many videos of Runs, Timeslips and Dyno runs showing that and more
And yes we even warranty them at those power levels no questions ask.

bortous

I have emailed you at frank@performabuilt.com

performabuilt

iTrader: (25)

Replied in email

bortous

I have decided I am going with Performabuilt black edition 4L65E for my build.
A lot of positive reviews and great testimonials.
I saw the build video and these guys really know their stuff.

Billiumss

iTrader: (11)

......

PBA

"Sonnax input drum reinforcement kit: You'll hear different sides to this story. In my opinion, it doesn't fix any problems. It just moves the problem to a different location."

What does it not solve? How does it move the problem to somewhere else?

MaroonMonsterLS1

The drum as a whole is weak. I've seen the bottoms of drums blow out even after this reinforcement.
I've seen the snap ring lugs pop off
I've seen the whole drum shatter
I've seen all sorts of things...but the failure rate of "stripped splines" is incredibly low in my personal experience.
I leak test every drum...and after a few years of doing so, I just preventatively press out each and every shaft, apply green loctite, and press back in.

I just don't see the benefit to pressing that collar on...as always Dana, I love to learn and hear other opinions. Why do you like it?

PBA

I agree with what you have seen and do. The breakage of this drum from it splitting open, is incredibly low. The only time I have actually seen it is in 4WD applications. I have heard of it happening with others in higher torque applications, and where the shifts at all throttle openings are hard. As you know I do not make anything shift hard. I use it as an "insurance measure".

MaroonMonsterLS1

Hard shifts=/= quality shifts
I applaud you for teaching a large population of people that fact.
Quick yet smooth...best for clutches and for hard parts

vorteciroc

Like Mr. Monsta, I also have seen quite a few units come in with this drum broken from other shops.

I have yet to have broken one, in our builds with or without the collar.
I feel proper turbine-shaft removal and re-installation in very important here.

When I do come across units, where this drum has failed... The units almost always have had all accumulator function removed.
I personally think that is a huge mistake...
If a builder can not figure out how to achieve the shift firmness that is desired, without removing all accumulator function; then what the hell are they doing, building these transmissions? I don't get it!

MaroonMonsterLS1

They're making easy money and offering no warranty!!
Uncle jim bob down the block can build his sister cousin's boyfriend a 60e for $600...why can't we?!