4L60E Pressure Regulator Valve (Boost Valve) (Part 1 of 3) (4L60E Line Pressure)
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- Опубліковано 4 вер 2024
- Learn how the 4L60E Pressure Regulator Valve (aka PR Valve) works. Get familiar with the 4L60E Boost Valve. Learn how the 4L60E line pressure is created.
Help this Channel Grow: • Help This UA-cam Chan...
**More 4L60E Videos**
Pump: • 4L60E Pump: How Does I...
PR Valve (Part 1): • 4L60E Pressure Regulat...
PR Valve (Part 2): • 4L60E Pressure Regulat...
PR Valve (Part 3): • 4L60E: PR Valve (Part ...
AFL Valve (Part 1): • 4L60E: AFL Valve (Part...
1-2 Shift Valve + Solenoid (Part 1): • 4L60E: 1-2 Shift Valve...
1-2 + 2-3 Shift Solenoid (Part 1): • 4L60E Shift Solenoid -...
Planetary Gearset: • Planetary Gearset - Ho...
Power Flow (OD Gears): • 4L60E Power Flow (1st,...
Power Flow: (Manual Gears): • 4L60E Power Flow - Man...
Teardown: • 4L60E Rebuild: Teardow...
Teardown Time-Lapse: • 4L60E Teardown (TimeLa...
Output Shaft Swap (2WD to 4WD Conversion): • 4L60E Output Shaft Swa...
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Over-Sized Pressure Regulator Valve: amzn.to/3CbAHm1
0.500" Boost Valve: amzn.to/3Af6ccP
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DISCLOSURE: 🕵
Links provided are affiliated links with the associated websites. While there is no extra cost to the purchaser, a small portion of the sale goes to support this UA-cam channel.
Thank you for being here!
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1 Handed Transmission Rebuilder (60 sec): ua-cam.com/video/ZQHtrVFUHdk/v-deo.html
Thankyou so much!!! My husband loves your videos! He said you are much better than his instructor at school
Wow, that's really nice!
I'm glad he is enjoying the videos. I appreciate your/his comment.
You’re an amazing teacher and this is the best video series I’ve seen explaining transmission components
Wow, thanks!
Hello Bob! I know that listening to your very easy to comprehend descriptions of the functions is WAY EASIER than looking in the tech manual at the different colors for fluid flow and functions! Thank you for helping all of us to understand in layman terms!
I've spent many a hour looking at hydraulic diagrams...talk about way too much going on, all at once. ha. I will be discussing the different colors for fluid flow, in a future video, to help make some sense of that. Thanks for bringing that up!
Thanks for dropping me a line, James. Always good to hear from you, man!
@@SouthpawAutoworks I was looking at the 4l60e tech manual last night for the first time. Your vids make this info accessible for sure. I didn't even try decipher the details in the manual.
Right on! That's nice to hear.
Thanks for dropping me a line!
I have been reading forums and watching videos for years, I have rebuilt 2 4l60e transmissions so far, but your videos are by far the best as they are the only ones I've seen that actually teach the fundamentals of how it actually works. I look forward to watching the rest of your videos.
I'm glad that you're enjoying them.
Clear&cut, Greeting from Bangkok,,,,,THANKS
Thank you.
Another great video. Thank you.
Thanks again!
Thank you, I learn so much from you!!!! I have 2 vehicles with 4L60e Transmissions in them, my '93 C1500 Pickup and my 2002 Chevy Trailblazer.... I always only know the 350 Turbo Hydramatic... These gearboxes (4L60e) were rare in South Africa due to the sanctions against SA.
That's wild... (sanctions).
It's really nice to hear that you're getting some value from these videos. I appreciate you letting me know.
Thanks for dropping me a line!
Fantastic video, super clear and detailed. I've learned a bunch.
You're my hero,,you have made my assignment easier
Right on! Glad to hear that.
It is 2pm now manila time, i didn't skip the ads, more power Rob
Joms F, you rock! Thanks for your support. I really appreciate it.
@@SouthpawAutoworks you are welcome bro, all the best
Great details
Excellent Presentation, You make my transmission learning process super easy.....Thanks a Lot and by the way just ready for the part # 2 and 3....
Glad it was helpful! Positive feedback is always appreciated.
Thanks for dropping me a line.
4L60E Pressure Regulator Valve (Boost Valve) (Part 2 of 3): ua-cam.com/video/dJlUec91kgY/v-deo.html
4L60E: PR Valve (Part 3) Torque Signal Oil Pressure (4L60E Line Pressure): ua-cam.com/video/PY1trZeLqTM/v-deo.html
4L60E: AFL Valve (Part 1) How it Works: ua-cam.com/video/LqBkdegPjNk/v-deo.html
4L60E Shift Solenoid - Part 1 (Basic Operation): ua-cam.com/video/FaChWmcsAgI/v-deo.html
4L60E: 1-2 Shift Valve + 1-2 Shift Solenoid (Part 1) Basic Operation: ua-cam.com/video/jPhm76RDz6Y/v-deo.html
Excellent Presentation
Epic production values as always!
Thanks, man! That means a lot, coming from you. =)
Thanks for stopping by and dropping me a line! Always good to hear from you, Rubidium.
Bro you inspire me to get off my fat ass and rebuild a transmission.!!! thank you!!
#Instruct&Inspire
I keep coming back to these videos. Well done. How about some on shift kits or the 4l80e?
Right on! I'm glad to hear that you're enjoying them/getting something out of them.
Would love to dedicate a video to modifying the 4L60E valve-body. It's on the to-do list.
Don't know if you're following the TH400 Build Series...but, there's a 4L80E on the bench, in the background...of a couple of those videos. Not sure when we will have time to get the 4L80E video put together....but, it's coming.
If you don't already know, the TH400 and the 4L80E are closely related. The 4L80E is basically a TH400, with an overdrive (4th gear) added to it, internally.
You can start getting familiar with the 4L80E by following the build series on the TH400.
TH400 Build Series: Updated
ua-cam.com/play/PLMK9OC5NGhbgVgAwDO_rCGFF38T1LjkS7.html
Thanks for being here.
Appreciate you taking the time to drop me a line.
Hey Mr Robert I have been working on my 4l60e for 6 months now on side of the road I have watched every video you have and it still won't work I need help man bad I'm starving and it's cold right now and I'm having to live in my truck with my dog until I fix it I'm 150 miles away from home and idk what else to do sir I just want to go home I rebuilt my transmission and it will only go in park reverse and neutral and this is my 5th time pulling it back out and I promise I'm not trying to get any sympathy I'm just needing advice on what the issue may be can you please help me out the only reason I'm asking you is because your awesome with these videos and I know you have the answer I'm just confused and lost and scattered brained right now
In regards to the cooling circut,My trans fluid was not circulating through the radiator due to being clogged, trans got extremely hot lost all gears due to seals being shrunken.Question is ,does the return fluid from cooler go directly to the bearings,bushings,planetaries and where else?
Excellent, excellent video
Thanks for dropping me a line!
PS - If it feels right to you, please help me spread the word about this channel. Here's some easy ways to share...
1 Handed Transmission Rebuilder: (60-Sec Preview)
ua-cam.com/video/y3Vixa_Ec1E/v-deo.html
How the 4L60E valve-body works: (60-Second Preview)
ua-cam.com/video/fWPSaLeaOXI/v-deo.html
Hello sir,please make a vedio on tcc solonied when and how its works thanks.
Would love to!
In good time.
Appreciate your interest in this topic.
Excellent Presentation! Do you only do the 4L60E transmissions? I searched and searched but could not find a video on your channel about installing a Transgo shift kit on a 4T65E! Do you have such a video?
At this point in time, no.
Unfortunately, no I do not.
Appreciate the positive feedback.
@@SouthpawAutoworks
Okay well I'm going to need you to make one now thank you!
@@SouthpawAutoworks
Just kidding about making the I am hysterical.
I'm quite the cut up
Haha
I'm picking up what you're putting down! ;)
Question
I have a 03 silverado z71 4wd
4l60e
It drives great but when you first crank it
It wont drive unless you rev it up a lot same for reverse
Its like it has no line pressure
But when you crank it and let it warm up then drive it it will do just fine
Ive checked the fluid its fine even put new filters . I dont know whats going on
My 2006 suburban 4l60e reverse stopped working. All forward gears still work perfect. When I put in reverse no weird noises but I can tell the trans is putting light torque to the rear driveline. Could this be the boost valve? Thanks Jeff.
Yes, it could be due to a worn out Boost Valve/sleeve. Depending on the year of the trans, you can drop the oil pan, and gain access to the Boost Valve.
There's other areas in the Reverse oil circuit, that could be leaking oil pressure, causing the clutches to slip/fail.
When time permits, I will be putting together a video on this topic.
so pressure regulator valve "creates" the pressure through restrictions, and the pressure control solenoid can create any pressure range based on amperage supplied to it, as long as it is built up beforehand?
PR Valve:
Yes. That's the idea.
Pressure Control Solenoid:
Amperage...yes. Create any pressure....not exactly.
There are a number of different oil pressures within the 4L60E. Line pressure is the highest (Created by the PR Valve).
There are other "mini" PR Valves in the trans, that take line pressure, and modify it to a lower pressure, for certain oil circuits.
I don't know if you're familiar with electrical systems on a car/truck. I like to think of it like 12V circuits, and 5V circuits.
At any rate...
The EPC Solenoid is fed an oil pressure that's lower than line pressure. The EPC Solenoid then dictates how much of that lower pressure will reach the Boost Valve.
Note: What I have written is not 100% accurate. I'm trying to keep things simple.
If you want to learn more, check out the 4L60E videos, listed below. They explain everything.
Really appreciate your interest in this topic.
Thanks for dropping me a line.
4L60E Pump - How it Works:
ua-cam.com/video/gJ5CdPJoJyg/v-deo.html
4L60E PR Valve - How it Works:
Part 1 - PR Valve: ua-cam.com/video/ELhJlZridIY/v-deo.html
Part 2 - Boost Valve: ua-cam.com/video/dJlUec91kgY/v-deo.html
Part 3 - Torque Signal oil pressure: ua-cam.com/video/PY1trZeLqTM/v-deo.html
4L60E AFL Valve - How it Works:
ua-cam.com/video/LqBkdegPjNk/v-deo.html
4L60E Shift Solenoid - How it Works:
ua-cam.com/video/FaChWmcsAgI/v-deo.html
4L60E Shift Valve - How it Works:
1-2 Shift Valve: ua-cam.com/video/jPhm76RDz6Y/v-deo.html
2-3 Shift Valve: TBD
3-4 Shift Valve: TBD
I had someone bench rebuild my 97 4l60e, now all forward gears shift great but reverse is slow to engage and slips.
That's a bummer.
Reverse is achieved by two clutch packs;
1). Reverse-Input Clutch.
2). Low-Reverse Clutch.
By the sound of things, for whatever reason, one of those clutch oil circuits is leaking oil pressure.
There's a way to identify which clutch/circuit is the problem, during a road test...through process of elimination.
Why was the trans rebuilt?
What was wrong with it before?
Great information 👍
Thanks for dropping me a line!
Can you damage the torque converter by over filling your transmission.fluid.
2nd question is When testing the shift solenoid and it makes no clicking noise is that means that the solenoid is not working
Torque Converter:
Over-filling the fluid level can raise the level high enough that the oil level comes into contact with rotating parts inside trans. Those rotating parts churn up the oil, injecting air into the fluid (air bubbles...known as aerating the fluid).
Air bubbles result in lower than normal oil pressures, and reduces the oil's ability to lubricate moving parts inside the trans (thrust washers/bearings, meshing gears, etc).
Shift Solenoid:
Yes. It should make a click sound when energized. If it's not, it may have a shorted winding inside the solenoid.
How exactly are you energizing it?
Are you testing solenoid while still in vehicle/trans, or on the bench?
If you're interested in learning more about the solenoid...
4L60E Shift Solenoid - How it Works:
ua-cam.com/video/FaChWmcsAgI/v-deo.html
great videos. I have a 1996 Fleetwood Cadillac the original transmission was replaced at 73K miles. Always changed fluids and filters every 20K miles. The replacement was an upgraded transmission which uses dextron 6 fluid. I also installed a trans fluid temp gage and an extra large trans fluid cooler. At 111K miles I lost 2nd gear shortly after its 2nd fluid and filter change. I removed the valve body and found the 1-2 valve not moving by hand. removed the valve, examined bore, valve and spring for damage, found nothing wrong. Decided to purchase a rebuilt valve body assembly from Amazon. Upon initial inspection the first two valves moved freely by hand by the 3rd and 4th one do not move at all. Is this normal or should I send it back as a defective unit before I install it? thank you in advanced for your help.
Hey can anyone tell me why my 2003 Yukon Denali has went through two transmissions both times I lose everything but first and reverse. I hate to get rid of this truck the motor is strong and the body is perfect and I've put a lot of money in it. But I'm scared to put another transmission in it in fear in 6 months to a year it'll be burnt up. Any advice
Question about my 03 4L80E in my GMC Sierra 2500hd. When the transmission temp is cool, all 4 gears will engage but 3rd and 4th are slipping while shifting. When it gets up to operating temperature, the transmission won't shift out of 2nd gear but 1st and reverse still work. No trouble codes are present, transmission fluid doesn't look or smell burnt. Is it a pump issue or a clutch issue?
Was hoping to respond sooner...
Sounds like a problem with the 3-4 clutch...which is one of the most common problems with this transmission.
If the trans is slipping, it will result in burnt fluid. Perhaps your shifting problem started happening recently.
Trans fluid gets thinner as it heats up. If there's an internal oil leak, it'll get worse as the trans heats up.
Were you able to find out more about your trans?
Hey Nice Video. Pls, can you tell me how much pressure we have Engine Idle no gear engange, just standing and Idle. And is the Pressure the same like the Pressure in the Cooling Line through the Trans cooler?
With the trans in Park/Neutral, you should have roughly 55 psi of Line Pressure.
The trans cooler is a byproduct of the torque converter.
Fluid path:
Oil pan to pump, pump to converter, converter to cooler, cooler to lube (planetary gearset), lube to oil pan....full circle.
With the TCC (Torque Converter Clutch) off (and the trans in Park/Neutral) I believe the cooler line will have line pressure present. But, I'm not certain...
Gonna have to look into this...
Thanks for dropping me a line!
In a 4l60e what controls converter charge pressure? (Not TCC apply/release) In a 4l80e its an a section of the pump.
I've been wanting to respond to your comment. Just haven't had time...until now.
I'm not sure that I understand the question. And I am interested in understanding.
You say "Not TCC apply/release."
I'm a bit confused by that part.
Anytime the engine is running, the 4L60E TC (toque converter) is being supplied with oil.
Oil is either being directed to the apply side of TCC (torque converter clutch), or it's being directed to the release side of TCC.
Which one are you referring to? Apply or release?
@@SouthpawAutoworks tcc apply and release.
We have a 4l60 that wiped the trust in a performance application.
The converter turns into a pump when on two step/launch it at 3200 (circle d converter with anti balloon plate)
On a th400 you restrict what would be tcc apply orrfice. Since i made this comment we found that transgo makes a 100psi tcc apply limiting valve and should resolve my issue!
Copy that.
Good deal.
Can I change the boost valve from sonnex with out removing trans or pump?
That's a great question. It is totally doable on units from 93-05. Some 06 units have an ISS (input speed sensor aka turbine sensor). 07-up units have ISS. Unfortunately the ISS gets in the way, and requires trans removal to replace the boost valve/sleeve.
When time permits, I'll put together a short video.
@@SouthpawAutoworks Tried to remove the boost valve from my chevy PU 1994, removed the snap ring, the sleeve moves a few milimeters outward but then stucks, any suggestion?
That's a great question. I have not had that issue before. But, I'm happy to assist.
When I get back to the bench, I'll look at my '93 4L60E and see if I can figure out what might be holding up the boost sleeve.
@@SouthpawAutoworks the problem was solved, grinding a bit of material(the "step") formed from wear from the bore with a dremel
Right on! Good eye...
I have rebuilt my 95 4l60E in s10. It shifts fine But acts like it’s low on fluid at idle. When you step on the gas at a light it takes a second to engage. Any help would be appreciated. Thanks Jerry.
Have you tried adding more fluid?
Best course of action would be installing an automatic transmission pressure gauge, and see what kind of pressures you're getting.
Should be right around 55 psi at idle.
Is this pretty much the same on a 700r4
The 4L60E and the 700-R4 are very similar.
I have a spin on filter kit I installed on my transmission do you think it would be good to install an upgraded pressure boost valve because of this? I installed the derale remote transmission filter kit. I mounted it under the airbox with some self tappers into the steel down there. Any other suggestions? It shift good doesn't seem to restrict any flow it is spliced into the cooler line coming out of passenger side. I have a 2001 Silverado 5.3 with the 4l60e.I used a good synthetic royal purple 20 micron oil filter.
Unfortunately, the pan filter doesn't do a great job of filtering small stuff out of the oil. However, an inline/external filter will be a nice addition to the pan filter.
Keeping the fluid clean is a great way to extend the life of the trans.
I do not believe it's necessary to upgrade the boost valve.
Hey sir. I installed a sonnex 4.90 boost valve in my 1994 camaro 4l60e trans had no problems before I do the install, I was just trying to firm up shifts. Now the trans is weak in reverse and shudders going forward. Have any idea what I did Wrong?
There's two (2) different boost sleeve lengths.
Might want to start there, and measure both, and see if there's a difference between the original and the replacement.
@@SouthpawAutoworks they were the same length. Is it possible that I installed the clip in the ring groove? Or is there only one groove that it can possible be installed in? The assembly went together almost too easy. I didn’t even have to hold the boost valve up while I installed the c clip.
I happen to have a '93 4L60E pump handy (it's the same as a 94).
The snap ring (c-clip) groove is located roughly 0.490" below the top of bore.
Note: The top of the bore isn't exactly flat, cuz it's located on the outside diameter of the pump. The measurement provided was taken on the driver-side of the bore...it's the shallowest side of the bore.
I've never had one go together that easy...
Sounds like something is missing from the valve-train.
@@SouthpawAutoworks thank you I will take the pan back off and investigate!
Were you able to get it fixed?
My 4L60E won't engage to D immediately.. It takes about 2-3 seconds.. But R is normal.. And after engaged to D it works fine. Gear changes normally.. Down shift is normal.. No slipping. Only to D from P or N is the problem..please help me with this problem
When time permits, I'll make a video that addresses this.
@@SouthpawAutoworks I'm having a similar issue, but it's the very opposite of this guy's problem. Mine is a 1988 700r4 that I rebuilt a few months back. .471 boost valve, 13 vane-pump, transgo jr kit, pinless accumulators, sonnax throttle valve (no 4-3 below %75 throttle), vette servo, hard part upgrades, dex 6, etc. Drive gears are very quick to engage but reverse takes about 5 seconds and then it will load up the engine. then after that when I give it throttle, I can feel it suddenly bump like the reverse clutches weren't all the way applied yet. ALL new seals, bushings and alto clutches. thanks for any input and I appreciate your generous, helpful videos on transmissions! it's becoming a lost art anymore.
I've got some ideas, but I better start with questions...
Questions:
1). Does this problem occur every time you start the vehicle, and shift from Park to Reverse? Engine cold? Engine warmed up?
2). Does the problem only occur after the vehicle has been parked overnight? Or parked for a few days?
3). After the vehicle has been parked overnight, if you start the vehicle, and skip Reverse, and shift immediately to Drive, is there a delayed engagement into Drive?
I know some of these questions may seem a bit odd, and possibly redundant. Bare with me. I'm trying to better understand what you're up against (and also rule some stuff out), so I can better serve you...as time permits.
Please answer each question. Thank you.
@@SouthpawAutoworks
1. It's an instant gear change to R and D when both engine and trans is cold/been parked overnight. slow to R but fast to D when warmed up/hot
2. R engages instantly/quicker when cold, overnight or few days either way. it still slightly bumps when I give it throttle, but not as loud as when it's warmed up.
3. I skipped R, (cold) and went straight to D and it engaged instantly. (I skipped all the way to 1st too and it made a cringe-worthy clunk sound)
I sure appreciate your help, I love figuring these things out. I am honestly not afraid to take it back apart again. it's all a learning experience and an interest for me. I grew up taking things apart and putting them back together as a toddler. (sometimes it'd be right.)
@@SouthpawAutoworks hi thank you for your concern..
Yes the problem happens every time. Even if it's cold start or engine is hot.
It takes 2-3 seconds to engage to the D.. Even drictly shiftes to 3,2,1..only R is engaging immediately. I can hear the engine rev changea but takes seconds to engage to forward movement.
What happens to the pressure if you file the pressure regular on the second opening after the pressurized pool that leads to tcc valve at 16:24? Transgo says it makes smoother regulation & longer converter life.
Please answer, Im putting mine back together.
You are correct. TransGo does say to do that, when installing their Shift Kit©. However......that is the case for the 700-R4, not the 4L60E. And yes, the two (2) transmissions are very similar.
If you're working on a 4L60E, and installing the TransGo kit, they do not instruct us to grind this land. The 4L60E land already has two flats (machined at the factory) on this land. The work is already done. ;)
TransGo is correct about smoother regulation and longer converter life. In the case of the 4L60E, if the valve land did not have the flats already ground into it...
1). It can make the PR Valve hyper sensitive to line pressure fluctuations (which are normal). This increased sensitivity causes the PR Valve to move back in forth, in the bore, more than necessary. This additional movement will wear out the bore prematurely. A worn out bore can lead to low line pressure, which can lead to smoked clutches.
2). It ensures that the torque converter (and the lube circuit) is fed oil at all times. This is not the case in all transmissions. During certain conditions, this limitation in other transmissions, can cause the Torque Converter and the planetary gear sets to overheat.
3). There's more to this....another topic, for another time.
Hope this helps.
@@SouthpawAutoworks Thanks yes it helps, I have a 4l60e an the pressure regulation valve does have the flat spot already but Im upgrading it to the sonnax oversized pressure regulator valve, I also installed the fitzall tcc valve which will block the pwm, which I really wasnt going for but Im gonna let it ride, but I learned it will increase line pressure. Im rebuilding my 4l60e back to stock but upgrading some of the valves in valve body an pump without reaming anything an accumulators are upgraded to pinless. Good videos.
Right on!
Maintaining line pressure is the key to clutch longevity.
Happy rebuilding.
I have a question, maybe it's already been answered, if so can you just direct me to the correct video? Anyway here it is, why is there a coast clutch?
Are you asking about a coast clutch for the 4L60E? Or for some other transmission?
@@SouthpawAutoworks The 4L60 I thought I heard you say Coast clutch. Correct me if I'm wrong. I'm trying to take in all of the videos. Hopefully I'll just absorb a lot of your knowledge. My rebuild will be in a month or so when I get back to Colorado
Thank you for clarifying.
I'm pretty sure I did say that ("Coast Clutch", on one of the 4L60E power flow videos). Let me correct myself. What I meant to say was Overrun Clutch.
The overrun clutch does a couple of things:
1). It adds more clutch plates (both frictions & steels), to assist the Forward Clutch (more holding power...less chance of clutch slippage).
2). It prevents the vehicle from coasting. In other words, it provides engine braking.
By design, the Input Sprag rotates freely in one direction, and yet it locks in the opposite direction. However, when the Overrun Clutch is turned on, it prevents the Input Sprag from rotating freely in any direction (the sprag locks in both directions).
The Overrun Clutch is turned on when the trans shifter is placed in D1, D2, & D3 modes. So, only the manual gears...not OD mode.
In manual gear modes, you'll get more clutch capacity, and you'll have engine braking.
In OD mode, you'll have no additional clutch capacity (it's not needed), and the vehicle will be able to coast (better fuel mileage).
I'll have to dedicate a video to this topic.
For the meantime, let me know what questions you have.
Line pressure. "it remain line pressure until ironically it isn't" 🙂
Right! haha
Turkçe language now