4l80 mods?
4l80 mods? I'm in the middle of putting in the sonnax line to lube valve in my 4l80 (stops the lock up clutches from dragging at idle) are there any valve body mods I can do while I'm in there.
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Depending on what horsepower you have here (350 FWHP), you would want to increase the holding power of 3rd gear by "dual feeding" it. If you are not going to take the transmission apart, then using the TransGo 4L80HD2 would be the way to go here. If it is apart then it could be a different way. Either way, add the 2004R low/reverse cup seals to both feed holes next to the center support bolt to stop the case to center support leaks. This can be done with the valve body removed.
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From: Turnin' Wrenches Infractions: 005
Hd2 here but we did it per Jakes recommendations. He detailed a list of the dos and don'ts of the kit. The dual feeding from what I've read is one of the main advantages of the kit. Off the top of my head we did that, drilled the new plate for firmer shifts, accumulator spring maybe, and replaced the thingy in the pump. The rest of the kit is not used.
Last edited by 01ssreda4; Sep 19, 2017 at 12:46 PM.
Originally Posted by PBA
Depending on what horsepower you have here (350 FWHP), you would want to increase the holding power of 3rd gear by "dual feeding" it. If you are not going to take the transmission apart, then using the TransGo 4L80HD2 would be the way to go here. If it is apart then it could be a different way. Either way, add the 2004R low/reverse cup seals to both feed holes next to the center support bolt to stop the case to center support leaks. This can be done with the valve body removed.
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From: Fort Worth, Texas
They are seals that came factory on TH200/200-4R transmissions to seal between the case & the Lo/Reverse Clutch Housing https://cobratransmission.com/200-4r...housing-2178-1
They can be used to seal the the feed holes on both sides of the center support bolt.
Requires 1 on a Internally dual fed 4L80E, 2 on a stock or externally dual fed unit.
Red arrow is 3rd/Reverse feed
Yellow arrow is Reverse feed....Gets plugged when internally dual feeding the directs.
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From: Fort Worth, Texas
However......If the Valve Body is torqued down correctly with a good wrench taking several passes, You won't have any problems!
I'll be the first to say....I DO NOT use HD-2 kits because they are a waste of money when rebuilding the unit. But for someone trying to make there trans hold-up without pulling it. The HD2 kit WORKS.
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From: Fort Worth, Texas
I do not use the 200 seals, I plug the reverse feed IN THE center support by driving a TV Exhaust checkball from a 700R4 in the support(bigger than a standard 1/4" ball)
File down what cast iron raised-up on the support from driving the ball in.
Chamfer the opening of the center support bolt hole.
Make sure the surface on the support edge between the case is good with no nicks/burs/raised spots.
Torque the center support down.
Drive a parking pawl cup plug into the reverse feed on the case side using retaining compound or red loctite. The reverse feed is now plugged on both sides.
The 3rd/Reverse feed will leak what it leaks, I don't have issues with direct frictions burning up.
Teching In
Joined: Feb 2006
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I do not use the 200 seals, I plug the reverse feed IN THE center support by driving a TV Exhaust checkball from a 700R4 in the support(bigger than a standard 1/4" ball)
File down what cast iron raised-up on the support from driving the ball in.
Chamfer the opening of the center support bolt hole.
Make sure the surface on the support edge between the case is good with no nicks/burs/raised spots.
Torque the center support down.
Drive a parking pawl cup plug into the reverse feed on the case side using retaining compound or red loctite. The reverse feed is now plugged on both sides.
The 3rd/Reverse feed will leak what it leaks, I don't have issues with direct frictions burning up.
File down what cast iron raised-up on the support from driving the ball in.
Chamfer the opening of the center support bolt hole.
Make sure the surface on the support edge between the case is good with no nicks/burs/raised spots.
Torque the center support down.
Drive a parking pawl cup plug into the reverse feed on the case side using retaining compound or red loctite. The reverse feed is now plugged on both sides.
The 3rd/Reverse feed will leak what it leaks, I don't have issues with direct frictions burning up.
i was instructed NOT to plug the reverse feed when doing the dual feed by JAKES Performance. they told me NOT to use any of the plugs. I did a stage 3 jakes kit, dual feed, rollerized bearing and upgraded hub and input shaft. also used there transbrake and plate.
I have done alot of research on 4l80es and from what I have seen its always recomended to rebuild them since the bushings seem to almost always be the first wear spots.
I have done alot of research on 4l80es and from what I have seen its always recomended to rebuild them since the bushings seem to almost always be the first wear spots.
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The "cup seals" work. They "fix" a leak. GM was going to use them many years ago, but for whatever reason, they passed on them. It was not their choice, according to the engineers that I talked too. TransGo also uses these cup seals in their regular 4L80E Shift kit.
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From: Fort Worth, Texas
i was instructed NOT to plug the reverse feed when doing the dual feed by JAKES Performance. they told me NOT to use any of the plugs. I did a stage 3 jakes kit, dual feed, rollerized bearing and upgraded hub and input shaft. also used there transbrake and plate.
I have done alot of research on 4l80es and from what I have seen its always recomended to rebuild them since the bushings seem to almost always be the first wear spots.
I have done alot of research on 4l80es and from what I have seen its always recomended to rebuild them since the bushings seem to almost always be the first wear spots.
If you have a aftermarket plate &/or a TB valve body & plate.....Follow their directions!
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From: Fort Worth, Texas
I wasn't disagreeing with you, I respect your input. I was just answering truthfully that I don't use the seals on internally dual fed units.
