TRNW-2: 68rfe Rev Max parts

Sat Nov 1 05:33:53 PDT 2025

 I do quite a few 68RFE's. I think I have put the tuneless kit in every one I have done since the kit came out. I would say a good percentage are tuned. I might have had 1 or 2 come back with broken input shaft,but I think that's it. We do usually try to sell the customer a sonnax input shaft but don't force it. I see the stock input shaft as a fuse. If the transmission gets abused the stock input shaft is what will fail.  And I have yet to see a broken input shaft take out other parts as far as I can remember.
 I won't do the sonnax "smart tech" OD drum anymore. I think they are on their 3rd or 4th part # (upgrade).  The last one I did I wouldn't have been able to make it stack up if we didn't have a lathe. I had to cut the reverse pressure plate where the snap ring goes to make it stack up. I called Sonnax about it. The way the guy I talked to with a quick reply and several answers that didn't work tells me I wasn't the first to call with an issue.  I also just don't think the little gain in clutch capacity/hydraulics you get is worth the money and hassle.
  But all said,I am not trying to brag. But I am just not seeing parts breakage from the kit. If there is parts breakage I believe it is from Mr. customer.
________________________________
From: trnw2-bounces at trnw.net <trnw2-bounces at trnw.net> on behalf of Steve Everett via trnw2 <trnw2 at trnw.net>
Sent: Saturday, November 1, 2025 7:05 AM
To: Tod Chretien <tod at trnw.net>; Technical Discussion Forum <trnw2 at trnw.net>
Subject: Re: TRNW-2: 68rfe Rev Max parts

   Tod,
         As I mentioned before I've installed that kit into numerous vehicles ever since it came out,  and I like the way it makes it shift,  but in the back of my mind I know there have been multiple parts breakages in units using that kit,  I'll still use it, but probably only on units I'm installing a billet input shaft, and someone's aftermarket input drum, among other changes,  as with most any modification done to increase output of either engine or transmission,   those type things only highlight the remaining "weakest" link in the power flow

   Steve

On Fri, Oct 31, 2025 at 6:41 PM Tod Chretien via trnw2 <trnw2 at trnw.net<mailto:trnw2 at trnw.net>> wrote:

Thank you for the post Robert. I have always loved the Tuneless kit myself and have never had any issues with it. I will continue to use it.

Tod

On 10/23/2025 6:55 PM, tranibob--- via trnw2 wrote:

Note sure where the 220 PSI advertised came from or who was involved in that so called consensus that our Tuneless™ kit could cause line to go much higher then 220 psi forward, but whoever it was simply does not understand how line pressure is regulated in an RFE.

Don’t just take my word for it, if you have any doubts, test it yourself to see it with your own eyes if you find hydraulic charts too difficult to follow. Pull the green wire out of the transmission connector going to pin 12 (line pressure solenoid control wire) or cut the wire and you will see that line will not go any higher than 172 psi on the scanner actual line pressure reading regular gauge if you trust that more at low RPM. During a WOT max RPM shift can sometimes make it go as high as high as high as 180 psi at the transducer if you push it real hard and you have no leaks anywhere.

172 psi at the transducer with our kit means you have 220 psi of actual line pressure and at 180 psi at the transducer you only have 234 of actual line pressure. That not even close to what you get with the popular 225 tunes and internal modifications or in even in the same ballpark as what you would get if you lost control of the line pressure solenoid with those modified unit. With our kit, there is no need for an added line pressure relief since the transmission cannot make more then 220-230 psi of line (RPM difference is what makes the range) in forward ranges.

We do have a limit built in for the lock-up pressure so not to damage the converter, it is set a 180 PSI whether you drill the hole in the pump as per the instructions or you install our drop in TCC ACCUM because that’s as high as you can go to increase the lock-up clutch capacity without putting the converter in danger.

The RFE pressure regulation unfortunately is quite different from more conventional PR systems we are used to, so it is easy to get scared for no reason when using a stronger PR valve spring and patented technology that makes the computer thinks the pressure is 30-32% lower than it actually is.

If you are breaking parts and wondering what caused it, don’t hesitate to product support at (626) 443-7451 during business hours or email us at support at transgo.com<mailto:support at transgo.com> (I answer all those emails) and we will be very happy to help you diagnose and find the root cause of the problem.

I can’t be on here and other online forums as I used to be and would like to be, due to different assignments at the company. That being said, if any of this is not clear don’t hesitate to ask questions on here or directly to my email, this stuff is not voodoo, consensus amongst some or not, I’ll gladly fill in the blanks and try and take all the mystery out of our any of our kit do what they do.

[cid:ii_19a3f4a07504cff311]<http://www.transgo.com/>

Robert Moreau

Technical Sales and Marketing Support Specialist

2621 Merced Avenue El Monte, CA 91733 USA

Calibration | Innovation |Performance

[cid:ii_19a3f4a07505b16b22]<https://www.facebook.com/TransGo-600961476956220> [1475592640337_I] <https://www.instagram.com/transgoshiftkit>  [1475592655171_t] <https://twitter.com/transgoshiftkit>  [1475592664972_Y] <https://www.youtube.com/channel/UCg6v9MzFmq7g3fy7-r9PGIg>  [1475592672363_L] <https://www.linkedin.com/company/transgo1/>

From: trnw2-bounces at trnw.net<mailto:trnw2-bounces at trnw.net> <trnw2-bounces at trnw.net><mailto:trnw2-bounces at trnw.net> On Behalf Of Tod Chretien via trnw2
Sent: Thursday, October 23, 2025 8:17 AM
To: trnw2 at trnw.net<mailto:trnw2 at trnw.net>
Subject: Re: TRNW-2: 68rfe Rev Max parts

Thank you Mark!

The shop I used to work for in Stockton just built a 68RFE with a tuneless kit and it came back with the input drum exploded. And the builder here at Ralphs (Rodney) won't use the tuneless kit because he claims he a had couple come back on him with broken components. I always figured they must have installed the kit in a tuned truck. However I just confirmed that the one they just built in Stockton only has 160 psi commanded line pressure in drive, so it's not tuned.

Things that make you go Hmmmmmm...

--

Best Regards,

Tod Chretien

TRNW Inc.

https://www.trnw.net

On 10/23/2025 6:59 AM, Mark Puccinelli wrote:

No pressure relief system built into the tuneless kits.

On Thu, Oct 23, 2025 at 6:47 AM Tod Chretien via trnw2 <trnw2 at trnw.net<mailto:trnw2 at trnw.net>> wrote:

> general consensus was sometimes those tuneless kits put out way more than the advertised 220 or so psi

Don't they have a pressure relief built into that tuneless kit? Maybe one of the Transgo guys can comment on this statement. Mark? Robert? Randy? You guys home? LOL

--

Best Regards,

Tod Chretien

TRNW Inc.

https://www.trnw.net

On 10/22/2025 12:40 PM, Steve Everett wrote:

    I've used both of those numerous times, but a little over a year ago I had a unit come back that had been out a few months,  the accumulators had blown out of the vb, pulling the heads off a couple of the screws and bending the plate a good bit, I posted about it on the forum, and general consensus was sometimes those tuneless kits put out way more than the advertised 220 or so psi ?

   I've probably got 12 or 15 68rfe's out there with my name on them using the tuneless kits,  that was the only one that caused a problem as far as I know ?   but I've been a little hesitant to use them since then

   Steve

On Wed, Oct 22, 2025 at 2:43 PM Tod Chretien via trnw2 <trnw2 at trnw.net<mailto:trnw2 at trnw.net>> wrote:

That seems over-kill if it's not tuned. I would use the Transgo Tuneless kit myself. They shift great with that kit. I also like that Transgo OD pressure plate that allows for an additional clutch.

--

Best Regards,

Tod Chretien

TRNW Inc.

https://www.trnw.net

On 10/22/2025 10:06 AM, Steve Everett wrote:

  I've seen the channel plate used in a couple shops I was at, by the other builder,  I've used the seperator plate on a lot of builds, even stock builds,  we've got a customer from out of town, broke down here, and he wants an upgraded rebuild, we're pricing him a Rev max drum, which comes already built ?  I didn't know that until I priced it, a billet input shaft and that valvebody kit,  the truck isn't tuned, totally stock, we are pricing in a billet converter of course,

  Steve

On Wed, Oct 22, 2025 at 12:59 PM Tod Chretien via trnw2 <trnw2 at trnw.net<mailto:trnw2 at trnw.net>> wrote:

I have used the separator plate and the channel plate but not their
accumulators. The channel plate is needed on anything with a tune.

--
Best Regards,
Tod Chretien
TRNW Inc.
https://www.trnw.net

On 10/22/2025 8:30 AM, Steve Everett via trnw2 wrote:
>    I have not used any of Rev Max's parts for these other than the
> bonded seperator plate,  has anyone used their 68rfe-347 valve body
> foundation build kit ?  comes with channel plate, seperator plate and
> billet accumulators,
>
> Steve
>
> This message was sent from the TRNW Technical Discussion Forum (trnw2). You were sent this message because you have subscribed to our mailing list. If you don't want to receive these emails from TRNW in the future, please unsubscribe here:
> https://www.trnw.net/unsubscribe.php?forum=2
> TRNW Inc., 2825 Walnut Terrace, Modesto, CA 95355

This message was sent from the TRNW Technical Discussion Forum (trnw2). You were sent this message because you have subscribed to our mailing list. If you don't want to receive these emails from TRNW in the future, please unsubscribe here:
https://www.trnw.net/unsubscribe.php?forum=2
TRNW Inc., 2825 Walnut Terrace, Modesto, CA 95355

--

[https://ci3.googleusercontent.com/mail-sig/AIorK4zYpBXtbbMKAyI95OMhPkV0zIjcZRiREhBRnpWdHx5pxhK0Jdh9todOdAq9AW1rcqiM2Bw-gEk]

Mark Puccinelli

Product Support Technician

TransGo

mark.puccinelli at transgo.com<mailto:mark.puccinelli at transgo.com>

Adjunct Driveline Professor

Skyline College

San Bruno,CA

puccinellim at smcc<mailto:puccinellim at smccd.edu>d.edu<http://d.edu>

Visit me on Facebook:

https://www.facebook.com/mark.puccinelli.7

[https://ci3.googleusercontent.com/mail-sig/AIorK4zqYBETLTQ7O7WsVuiaz5M7DyFKAOmbWT7vhKpQDDJBCzn-YtVnaVqSS3y7Qvj1k-1jCyZAw0w]

--

Best Regards,

Tod Chretien

TRNW Inc.

https://www.trnw.net

This message was sent from the TRNW Technical Discussion Forum (trnw2). You were sent this message because you have subscribed to our mailing list. If you don't want to receive these emails from TRNW in the future, please unsubscribe here:
https://www.trnw.net/unsubscribe.php?forum=2
TRNW Inc., 2825 Walnut Terrace, Modesto, CA 95355

--
Best Regards,
Tod Chretien
TRNW Inc.
https://www.trnw.net

This message was sent from the TRNW Technical Discussion Forum (trnw2). You were sent this message because you have subscribed to our mailing list. If you don't want to receive these emails from TRNW in the future, please unsubscribe here:
https://www.trnw.net/unsubscribe.php?forum=2
TRNW Inc., 2825 Walnut Terrace, Modesto, CA 95355
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.trnw.net/pipermail/trnw2/attachments/20251101/d39cc252/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 12854 bytes
Desc: image001.png
URL: <http://lists.trnw.net/pipermail/trnw2/attachments/20251101/d39cc252/attachment-0006.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.png
Type: image/png
Size: 431 bytes
Desc: image002.png
URL: <http://lists.trnw.net/pipermail/trnw2/attachments/20251101/d39cc252/attachment-0007.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.png
Type: image/png
Size: 1135 bytes
Desc: image003.png
URL: <http://lists.trnw.net/pipermail/trnw2/attachments/20251101/d39cc252/attachment-0008.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image004.png
Type: image/png
Size: 463 bytes
Desc: image004.png
URL: <http://lists.trnw.net/pipermail/trnw2/attachments/20251101/d39cc252/attachment-0009.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image005.png
Type: image/png
Size: 394 bytes
Desc: image005.png
URL: <http://lists.trnw.net/pipermail/trnw2/attachments/20251101/d39cc252/attachment-0010.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image006.png
Type: image/png
Size: 414 bytes
Desc: image006.png
URL: <http://lists.trnw.net/pipermail/trnw2/attachments/20251101/d39cc252/attachment-0011.png>