4L60e - No engine braking, only in Manual 1st
TECH Junkie
Joined: Jun 2008
Posts: 3,194
Likes: 1,377
From: Nitro Alley
Only the Reverse-Input Clutch applies, and the Low-Reverse Clutch Fails?
(Low-Roller is not of question here).
You guys have Posted Hydraulic Diagrams...
Put some Power-Flow Diagrams UP from the same Material/ Book.
Thread Starter
Teching In
Joined: Aug 2011
Posts: 14
Likes: 1
Okay, I've been doing some more studying. Thanks for pushing me in the right direction without spoon feeding me the answers 
Here is confirmation I should be looking at the low/reverse clutch. Those who suggested this were correct, of course
Highlighted in yellow.
I now also know I shouldn't be assuming the low/rev clutch is okay just because reverse works as it is applied differently when in M1.
Surely I didn't mess up the very first piston seal that went into the case!?!? It's beginning to emerge as a good possibility. Sigh...
Although, even if that seal was damaged, wouldn't the piston still apply as fluid filled the cavity up to the 'outer seal'?
Highlighted in yellow.
I think I'll have to drop the pan to check the 'stiffener plate' above the A/B solenoids, then maybe go looking at the low/reverse position 'center seal' in the above drawing.
Am I heading in the right direction?
Here is confirmation I should be looking at the low/reverse clutch. Those who suggested this were correct, of course
Highlighted in yellow.
I now also know I shouldn't be assuming the low/rev clutch is okay just because reverse works as it is applied differently when in M1.
Surely I didn't mess up the very first piston seal that went into the case!?!? It's beginning to emerge as a good possibility. Sigh...
Although, even if that seal was damaged, wouldn't the piston still apply as fluid filled the cavity up to the 'outer seal'?
Highlighted in yellow.
I think I'll have to drop the pan to check the 'stiffener plate' above the A/B solenoids, then maybe go looking at the low/reverse position 'center seal' in the above drawing.
Am I heading in the right direction?
TECH Junkie
Joined: Jun 2008
Posts: 3,194
Likes: 1,377
From: Nitro Alley
Obviously the Planet will not be held still by the Low-Reverse Clutch...
How will the Transmission/ Vehicle behave?
What is the difference between the Pinion Gears Rotating with the Planet held VS the Pinion Gears Rotating and the Planet Rotating?
How will the Transmission/ Vehicle behave?
What is the difference between the Pinion Gears Rotating with the Planet held VS the Pinion Gears Rotating and the Planet Rotating?
TECH Junkie
Joined: May 2012
Posts: 3,046
Likes: 713
From: Poplarville, MS
Thread Starter
Teching In
Joined: Aug 2011
Posts: 14
Likes: 1
Lol, this thread has become an academic discussion.
I'm going to drop the pan to check the stiffener plate is bolted down properly. If it is, I'll drop the VB and air check the lo/rev piston via this hole:
I hope this will show a leak somewhere to explain why my line pressure is a bit lower than expected in reverse, and why the low/rev clutch isn't applying properly in M1
Sound reasonable?
I'm going to drop the pan to check the stiffener plate is bolted down properly. If it is, I'll drop the VB and air check the lo/rev piston via this hole:
I hope this will show a leak somewhere to explain why my line pressure is a bit lower than expected in reverse, and why the low/rev clutch isn't applying properly in M1
Sound reasonable?
TECH Junkie
Joined: Jun 2008
Posts: 3,194
Likes: 1,377
From: Nitro Alley
Alright, I feel like people are just guessing...
And that is better than No One trying at all!
But the Answers to My simple Questions are right there in the Books that you guys are posting from.
Read what there...
and Post your Proof!
And that is better than No One trying at all!
But the Answers to My simple Questions are right there in the Books that you guys are posting from.
Read what there...
and Post your Proof!
TECH Junkie
Joined: Jun 2008
Posts: 3,194
Likes: 1,377
From: Nitro Alley
Lol, this thread has become an academic discussion.
I'm going to drop the pan to check the stiffener plate is bolted down properly. If it is, I'll drop the VB and air check the lo/rev piston via this hole:
I hope this will show a leak somewhere to explain why my line pressure is a bit lower than expected in reverse, and why the low/rev clutch isn't applying properly in M1
Sound reasonable?
I'm going to drop the pan to check the stiffener plate is bolted down properly. If it is, I'll drop the VB and air check the lo/rev piston via this hole:
I hope this will show a leak somewhere to explain why my line pressure is a bit lower than expected in reverse, and why the low/rev clutch isn't applying properly in M1
Sound reasonable?
(Normal for M1/ 1st Position)
(The reverse Position will also use the #12 Passages, through the #10 Check-Ball to fill the Greater-Chamber of the Low-Reverse Clutch Apply Piston.
I would also look at those corresponding Passages in the Valve-Body to the Low-Overrrun Valve (it is crucial) as control dictates if One or Both Chambers of the Piston are filled for Reverse use/ M1/ 1st use.
Thread Starter
Teching In
Joined: Aug 2011
Posts: 14
Likes: 1
Thank you, much appreciated.
Yes I did note that low-overrun valve was involved and planned to test it was free to move in the VB.
On p65. of the manual it states:
-Spring force holds the lo overrun valve open and lo/1st fluid is
routed through the valve to fill the lo/reverse fluid circuit.
Yes I did note that low-overrun valve was involved and planned to test it was free to move in the VB.
On p65. of the manual it states:
-Spring force holds the lo overrun valve open and lo/1st fluid is
routed through the valve to fill the lo/reverse fluid circuit.
Thread Starter
Teching In
Joined: Aug 2011
Posts: 14
Likes: 1
Also... what will happen when in the Reverse Position, if:
Only the Reverse-Input Clutch applies, and the Low-Reverse Clutch Fails?
(Low-Roller is not of question here).
You guys have Posted Hydraulic Diagrams...
Put some Power-Flow Diagrams UP from the same Material/ Book.
Only the Reverse-Input Clutch applies, and the Low-Reverse Clutch Fails?
(Low-Roller is not of question here).
You guys have Posted Hydraulic Diagrams...
Put some Power-Flow Diagrams UP from the same Material/ Book.
I can see now why you have posed this question, but I don't have a clear enough understanding of how all the mechanical parts interact to provide an intelligent answer.
I'd love to know though, as I can now see how this would aid my diagnostics!
Thread Starter
Teching In
Joined: Aug 2011
Posts: 14
Likes: 1
Fixed!!
It was missing the spring from the lo-overrun valve! So the valve was pushed into the Park-Rev position and was unable to return to the lo-1st position.
I actually built this transmission about 12 years ago and only just put it in the car two weeks ago.
So I really don't remember what I did at the time or how that may have happened. The trans came from a breakers yard, so who knows.....
Thanks to all those who helped!
It was missing the spring from the lo-overrun valve! So the valve was pushed into the Park-Rev position and was unable to return to the lo-1st position.
I actually built this transmission about 12 years ago and only just put it in the car two weeks ago.
So I really don't remember what I did at the time or how that may have happened. The trans came from a breakers yard, so who knows.....
Thanks to all those who helped!
Registered User
Joined: Apr 2026
Posts: 1
Likes: 1
Okay, I've been doing some more studying. Thanks for pushing me in the right direction without spoon feeding me the answers
Here is confirmation I should be looking at the low/reverse clutch. Those who suggested this were correct, of course
Highlighted in yellow.
I now also know I shouldn't be assuming the low/rev clutch is okay just because reverse works as it is applied differently when in M1.
Surely I didn't mess up the very first piston seal that went into the case!?!? It's beginning to emerge as a good possibility. Sigh...
Although, even if that seal was damaged, wouldn't the piston still apply as fluid filled the cavity up to the 'outer seal'?
Highlighted in yellow.
It is getting incredibly difficult to tell if an article was written by a human or a machine. I have tried several different platforms to check freelance submissions, but my favorite is the brisk AI detector online because it works instantly without complex settings. The accuracy rate is very high, making it my primary tool for verifying content quality nowadays.
I think I'll have to drop the pan to check the 'stiffener plate' above the A/B solenoids, then maybe go looking at the low/reverse position 'center seal' in the above drawing.
Am I heading in the right direction?
Here is confirmation I should be looking at the low/reverse clutch. Those who suggested this were correct, of course
Highlighted in yellow.
I now also know I shouldn't be assuming the low/rev clutch is okay just because reverse works as it is applied differently when in M1.
Surely I didn't mess up the very first piston seal that went into the case!?!? It's beginning to emerge as a good possibility. Sigh...
Although, even if that seal was damaged, wouldn't the piston still apply as fluid filled the cavity up to the 'outer seal'?
Highlighted in yellow.
It is getting incredibly difficult to tell if an article was written by a human or a machine. I have tried several different platforms to check freelance submissions, but my favorite is the brisk AI detector online because it works instantly without complex settings. The accuracy rate is very high, making it my primary tool for verifying content quality nowadays.
I think I'll have to drop the pan to check the 'stiffener plate' above the A/B solenoids, then maybe go looking at the low/reverse position 'center seal' in the above drawing.
Am I heading in the right direction?