MY_2K_Z

iTrader: (1)

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.

MY_2K_Z

iTrader: (1)

Well did some research and it looks like I can drill out the separator plate for the 1-2 2-3 shifts to firm them up.

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.

kingtal0n

iTrader: (1)

And Dana does it again. HD2 kit here as well on his recommendation.

Long live probuilt automatics!

01ssreda4

iTrader: (96)

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.

MY_2K_Z

iTrader: (1)

More like 700rwhp and the trans is still in the car I just figured there might be some easy stuff I could do while I have the pan off. I plan to do the separator plate mods but that's about all I can do without ordering parts which I don't have the time to wait. So I guess that will just have to do

subeone

iTrader: (5)

dont do the hd2 kit. The separator plate leaks. Do the dual feed mod instead.

Mo6893

Hadn't heard that one.

Any additional info?

clinebarger

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.

clinebarger

While it's possible that the triple layered plate can cause minor crossleaks.
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.

Mo6893

Is that something you bother with? With dual feed, would it not still have the same leak path on the feed side that is plugged coming from the center support?

clinebarger

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.

Mo6893

That'll fix it!

82cetuner

iTrader: (9)

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.

PBA

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.

clinebarger

If your using a Stock or Stock replacement Separator Plate on a Stock 4L80E & your internally dual feeding the directs....You must plug the reverse passage at the center support or plug the feed orifice in the plate or you will have a major 3rd/Direct apply leak.

If you have a aftermarket plate &/or a TB valve body & plate.....Follow their directions!

clinebarger

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.

Krom

whats the best way to internally dual feed?

clinebarger

That's a loaded question! What is the use? Automatic Shift? Stock Valve Body?

82cetuner

iTrader: (9)

i did my own internal duel feed. just drill a hole in the drum and ommit 2 seals