TRNW-2: 6L80e performance builds ?

[jbockus at hiwaay.net]

Steve, To be honest, I NEVER use Raybestos either, as a matter of fact, 
this was only the 2nd 6L80 transmission that I had ever built so I was 
hesitant to take the job in the first place but I did with the 
understanding that the only warranty was that it worked out the parking 
lot. This is the only 6L80 that I have used the Raybestos clutches in 
and will not use them again. But since I had little experience on these 
at the time and he provided his own parts, I went ahead and used them. 
It was also a great learning experience!

On 2025-10-21 6:29 am, Steve Everett wrote:
> I've seen a couple of kits online advertised as "performance" kits,
> basically the same stuff we use on occasion ,  I'm surprised that kit
> came with Raybestos frictions ?   I won't use them in a 6L80, or most
> anything else either,  if I have a choice ,  I mainly use B&W ,  Exedy
> when I have to,   if we decide to build the unit for this guy I'll use
> BW frictions,  the billet planet and the billet 4-5-6 hub,  I'm going
> to give all this info to the manager and let him work up a price for
> the guy,  we'll see?   He's spent money on the engine, maybe he'll be
> willing to do the same for the trans ?
> 
>    Thanks guys,
>                       Steve
> 
> On Tue, Oct 21, 2025 at 7:18 AM <jbockus at hiwaay.net> wrote:
> 
>> I've done one on a 13 GMC Sierra 4x4 with a supercharged 6.2
>> producing
>> 700 rwhp. The customer supplied their own performance rebuild kit
>> which
>> included the Sonnax 4-5-6 hub, Sonnax billet 1-2-3-4 piston, Sonnax
>> HD
>> 4-5-6 apply piston kit and a Sonnax Sure-Cure kit. It also came with
>> 
>> Raybestos clutches and kolene steels and all bushings and bearings.
>> He
>> had also ordered a billet torque converter but I forget the stall,
>> he
>> wasn't happy with the stall and we ended up replacing the converter
>> with
>> a PTC billet converter and I don't remember the stall on it either.
>> He
>> originally had someone that I am unfamiliar with tune it and he
>> wasn't
>> quite happy, so I referred him to our local tuner, Tommy Blackard
>> who
>> works for PTC and he was able to get another 150 HP out of the
>> engine by
>> just tuning! This truck is bad-ass! It is his daily driver but he
>> does
>> take it to the drag strip on the weekends. I built it about 4-5
>> years
>> ago and it's still running strong. By the way, the Raybestos
>> clutches
>> caused a 2-3 squawk which was eliminated with 2 tubes of Lubeguard
>> shudder fix.
>> 
>> On 2025-10-21 5:41 am, Fred Whitaker via trnw2 wrote:
>>> I have never done any "performance" 6L80's either. But I did the
>>> Transgo kit once in a big box truck.  I wasn't all that impressed.
>> It
>>> was back when they first came out.  I remember the shifts not
>>> matching. (some were almost harsh,while others seemed normal)
>> That
>>> said I didn't HP tune it,which is probably why.
>>> Intermediate shaft (or 456 shaft) is the second thing that comes
>> to
>>> mind as weakest link. Torque converter would be #1 and is where I
>>> would spend a big part of the money.
>>> 
>>> -------------------------
>>> 
>>> From: trnw2-bounces at trnw.net <trnw2-bounces at trnw.net> on behalf of
>>> Steve Everett via trnw2 <trnw2 at trnw.net>
>>> Sent: Monday, October 20, 2025 9:02 AM
>>> To: Technical Discussion Forum <trnw2 at trnw.net>
>>> Subject: TRNW-2: 6L80e performance builds ?
>>> 
>>> We have an insurance inspector inquiring about his own personal
>>> truck,  which has a 5.3 with twin turbos !  I've not done any
>>> "peformance" builds on 6L's as of yet, haven't had anyone ask
>> really,
>>> I know there is a heavy duty 4-5-6 hub and shaft, but I thought
>>> someone might have come up with some stronger 3/5/r or 1/2/3/4
>>> hub/shafts by now ?  but I've not seen any in a quick search,
>>> transgo has their tow n pro kit
>>> 
>>> Anyone done any performance stuff on 6L's ?  what did you use ?
>>> 
>>> Steve
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