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SKU #: PPE-128041119 MPN #: 128041119

PPE EPC Blocker Allison 1000 11-19 GM 6.6L LML L5P Duramax

$47.02$49.49
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PPE EPC Blocker Allison 1000 for 11-19 GM 6.6L LML L5P Duramax
PPE EPC Blocker Allison 1000 for 11-19 GM 6.6L LML L5P Duramax
Description
One of the biggest issues with the transmission in your 2011-2019 GM Duramax is low mainline pressure created by the transmissions oil pump. Mainline pressure is directed by the valve body to the apply pistons and creates clamping force on the clutch packs, allowing the clutch packs to clamp quickly and completely. Reduced mainline pressure, or not having enough mainline pressure at the right time means reduced clamping force and there won't be enough to hold the torque of the engine. When clutch packs slip they generate excessive heat which destroys the clutch pack material. The stock EPC functions to modulate line pressure. During a shift, the transmission control module commands the EPC to vary mainline pressure. The pressure will rise from 80psi up to 230psi. After the shift, the pressure drops back down to 80psi. At 80psi the clutch packs don't hold the torque of the engine. Towing heavy loads or adding aftermarket upgrades adds even more stress on the clutch packs. The EPC blocker kit quickly installs between the EPC solenoid and the valve body. There is no need to remove the valve body. Just drain the transmission fluid and remove the oil pan and install the EPC blocker. Once installed, the EPC blocker will allow all the available mainline pressure, up to 230psi, to reach the apply pistons and clutch packs at all times.

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One of the biggest issues with the transmission in your 2011-2019 GM Duramax is low mainline pressure created by the transmissions oil pump. Mainline pressure is directed by the valve body to the apply pistons and creates clamping force on the clutch packs, allowing the clutch packs to clamp quickly and completely. Reduced mainline pressure, or not having enough mainline pressure at the right time means reduced clamping force and there won't be enough to hold the torque of the engine. When clutch packs slip they generate excessive heat which destroys the clutch pack material.

The stock EPC functions to modulate line pressure. During a shift, the transmission control module commands the EPC to vary mainline pressure. The pressure will rise from 80psi up to 230psi. After the shift, the pressure drops back down to 80psi. At 80psi the clutch packs don't hold the torque of the engine. Towing heavy loads or adding aftermarket upgrades adds even more stress on the clutch packs.

The EPC blocker kit quickly installs between the EPC solenoid and the valve body. There is no need to remove the valve body. Just drain the transmission fluid and remove the oil pan and install the EPC blocker. Once installed, the EPC blocker will allow all the available mainline pressure, up to 230psi, to reach the apply pistons and clutch packs at all times.

EXECUTIVE ORDER #CA
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Vehicle Fitment
2011-2019 GM 6.6L LML L5P Duramax
WARNING: Cancer & Reproductive Harm - P65Warnings.ca.gov
About PPE (Pacific Performance Eng.)
Browse PPE Diesel Parts Online by Make, Model, and Year. Originally founded in 1985, Pacific Performance Engineering (PPE) is leading the way in the progression of diesel performance. Their roots started them in the diesel performance industry installing other manufacturers kits and components, which led to the release of their original product, the Duramaximizer, in 2001 to improve upon the power and efficiency of the LB7 Duramax, and is still in use today. Today, they are known for manufacturing dual CP3 kits, their line of Xcelerator programmers for numerous applications, upgraded oil pans, and nearly anything you can think of to improve the power and extend the life of your Duramax, Cummins or Powerstroke.
Video
DIESEL TALK | PPE EPC BLOCKER!
Watch how this simple yet powerful upgrade transforms your Allison 1000 transmission performance. The EPC Blocker eliminates pressure drop-off between shifts, maintaining full mainline pressure (up to 230 psi) at all times to protect your clutch packs from slippage and heat damage under heavy towing loads and high-performance conditions. No valve body removal required. Installation takes minutes, but the protection lasts for years.
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Overall rating: 4.6153846 / 5 from 13 reviews.

AI Generated Review Summary

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Review highlights

Reviews

PPE ECP Blocker Night and Day Difference!

"I wish that i hadn’t waited so long to do this upgrade. The installation was easy and I also went with the Banks Air-Ram transmission pan as well. The shifting is a night and day difference! If you’re thinking about, do it."

— Clint D. (4/5)

EPC Blocker is a game changer

"I installed the EPC Blocker and a PPE deep transmission oil pan and filer kit. My Allison T1000 shifts crisp and firm now . especially while towing my 16,000 lbs 5th wheel trailer."

— James H. (5/5)

Works as it should. Improved

"Works as it should. Improved my shift quality and good to know the line pressure is increased and all around a peice of mind. Super easy install"

— Dustin C. (5/5)

Works great.

"Works great."

— Pat K. (5/5)

Progressively increase as power added,

"Progressively increase as power added, logical solution 👍"

— Roger A. (5/5)

EPC Blocker

"Like the idea of full line pressure to help this Allison survive as long as possible. If you are debating on buying this don't hesitate. Well worth the money. Don't know why I waited so long. Thanks DPP"

— Dale G. (5/5)

Great product

"Installed this on my 2011 and it made my trans shift much better and smoother…it will make your trans run a little hotter with the line pressure being increased but I love it"

— Jake S. (5/5)

Shipping Very BAD!

"Shipping Very BAD!"

— Raymond T. (1/5)

Delivery issue.

"I had a delivery issue. They got right on it and corrected the problem immediately. Thanks."

— Andrew Z. (5/5)

Shifts Great.

"Clean, crisp shifts notice torque converter lock up is smoother and keeps rpm in the power range. The torque output is consistent in between shifts and doesn’t make the rpm’s drop under the charger like it did when pressure would drop."

— Brian A. (5/5)

Q&A

Would this cause any issues with a L5P with 210000 miles on it
As long as the vehicle has been maintained well, I cannot a reason you would have issues running this EPC blocker.
Just installed this in my 2017 Duramax, followed all instructions, and now all of my gears are blinking. Please help!! Will not go into any gear. Thanks, jeremy
More than likely an electrical connection is not properly connected/attached to one of the solenoids. Getting a scan tool to see if there is a communication failure will tell you or dropping the pan and looking will answer that. If you have other questions or need help please feel free to shoot us a call. -Mark
How much firmer are shifts are they comfortable enough for daily driver
This will give you the capability of upping the line pressure to 230PSI at wide open throttle. Otherwise you should still have quality shifts while driving around. When you are really laying into the truck you'll feel it firm up a bit but nothing unbearable. -Mark
I have a 2011 duramax that has an enhanced tcm from dans diesel will the epc blocker still work
I can't imagine it would hurt anything. But that is more for a truck with stock TCM that doesn't raise line pressure. I'm sure Dan's Diesel raises the line pressure. -Sands
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