4L80E TRANS QUESTIONS

[1-ton]

I have been pulling apart my 4l80E transmission valve body and inspecting it. I inspected it for galling in the valve body check ball area, and It definitely has a small amount of galling in the check ball location 3 and 4 (as shown in diagram below). The separator plate shows galling in the corresponding 3 and 4 check ball locations too. No other galling is present.

I am definitely going to be replacing the separator plate. It looks like a light pass with my small die grinder should clean the galling away from the case side valve body channels. Would this assumption be correct?

I also bought some Sonnax .250 imidized plastic check balls for my valve body. These are supposed to eliminate the galling problem in the future.

 

[1-ton]

When I buy a separator plate I am going to buy the Transgo 4L80E-HD2 kit. The reason for this is it comes with a dual separator plate set-up. This dual separator plate set-up allows the trans to "dual feed", thus curing known problems the 4L80E trans is known for. After doing some research, this way of duel feeding the 4L80E trans is not the best, but will do for now until I rebuild it, and internally dual feed my trans via the internal direct clutch instead.

When I buy the Transgo kit I do not want to drill the pressure relief holes in the valve body, which Transgo recommends because I have read this modification can cause erratic line pressures. I am also not interested, at this time, in increasing shift firmness so I will not do the other mods in the Trango kit. The thing I am mostly after is Transgo separator plates.

I also bought and installed a Sonnax boost valve kit (PN# 34200-10k), which also fixes some of the known line pressure problems with the 4L80E. Are there any suggestions or input from trans experts...like Greg Ducato.

 

[76zimmer]

Greg would be the one to ask....I have 230K on mine in my 99-2500....I gotta say its been overworked for what the truck is, but its still going strong!

 

[Greg Ducato]

The TG kit is pretty good, do not do the pressure bypass mod. The TG kit has a new PR valve similar to the Sonnax piece, we like the Sonnax valve

 

[1-ton]

The TG kit is pretty good, do not do the pressure bypass mod. The TG kit has a new PR valve similar to the Sonnax piece, we like the Sonnax valve

Should I do a light grind on the trans case side of the valve body to get rid of the small galling ridge formed by the check balls in posistion 3 and 4. or leave as is? Also, shift kit companies recommend removing the reverse check ball from the case side located in position 9 in the case valve body diagram. Because I am not intending on doing any shift firmness improvements at this time, should I even bother removing this check ball?

 

[Greg Ducato]

Follow the kit instructions except for the pressure release mod discussed. Just knock any loose flashing off any ridge and leave the rest alone.

 

[azblazer]

I bought a new gm valve body complete from ebay for 125 bones. Added the HD2 kit and one of greg's awesome torque convertors and i am very pleased.

 

[1-ton]

Follow the kit instructions except for the pressure release mod discussed. Just knock any loose flashing off any ridge and leave the rest alone.

Thanks. There will probably be more questions in the future because I am focusing on the trans part of my engine build right now. I had a local guy, who has the equipment to open up torque converters and rebuild them, put a billet steel piston and stator in my OE torque converter core. He also put in new lock-up clutch lining in it.