4L80E Build questions

[Lumpofcole]

Hello,

Hoping Cline can chime in. I'm in the middle of my second 4l80e build (2000 model), this ones for a friend this time. Were using a CK performance master shift kit on this one. 2 dumb questions on this kit as I haven't used this kit before:

1) the direct drum th400 piston in the kit did not come with lip seals. The rebuild kit I ordered for this build (Alto HEG kit from ebay Cline recommended in other threads) came with molded pistons and lacked the lip seals for for the drums used in earlier models. I have the lip seals for early 4l80e left over from my first build (I used a probuilt kit from Dana on 1st build). Will these lip seals work fine? I test fit them and they fit perfect, seems good to me. Only reason I'm asking a search on LS1tech someone asked the same question and someone said not to use them on the th400 drum(no explanation given of course!).

2) the CK Kit uses a 4l80e front pump cover bushing for rear output shaft for rollerizing. I used your method on my first build by knocking in a no walk bushing from the rear and a TH350 pump needle bearing (working great thanks!). Are there any issues using the CK method as there is no lube circuits in the pump busing?

 

[clinebarger]

Some 4L80E kits have Short Lip style lip seals & that's likely what they were talking about, I prefer the TH400 style with the longer lips......However, I've never had an issue outside of extreme pressure spikes that would blow the seals out.....At that point lip seals are the least of your worries.

The factory 4L80E Case bushing doesn't have lube flutes in it either....But I would prefer to use either a TH400 Case Bushing or the Sonnax No-Walk to ensure adequate lube to the Bearing.

 

[Lumpofcole]

Thanks for response! I have an extra no walk on hand, any issue with using it with the supplied bearing in the CK kit?

Also will be using a 6th clutch and steel in the direct, I should be removing the waved in this drum correct?

 

[Lumpofcole]

Didn't have a TH00 seal to compare with, went ahead and used what lip seal I had on hand for the direct piston, worked nice, stacked direct on center support and air checked, had great seal it seems. Stacked my direct up with the 6 clutches and steels and omitted the wave in this drum. Clearance is tight! Barely fit "0.040 guage feeler in there. Also dry fit the Sonnax no-walk bushing around the bearing from the CK kit, was pretty tight but looks like it will work out fine.

 

[clinebarger]

.040" is too tight on a 6 clutch Direct, They overrun at 2.5 times engine RPM in 1st gear & will burn up without sufficient clearance.

 

[Lumpofcole]

Ok, so I checked the clearance in my forward and got about .080". Would it be alright to swap a .077" steel from the forward with steel from the direct? What clearance would you recommend to be at in a 6 clutch direct?

 

[Lumpofcole]

So I did swap out 2 steels between the direct and forward, now have 0.055" clearance in the direct and 0.065" in the forward.

 

[clinebarger]

That'll work ......You could tighten up the Forwards a bit by swapping in a Direct steel.....The Forward will run as tight as .030" & be fine.

 

[Lumpofcole]

Ok so my buddy had this 4l80e I built finally installed(not by him but by a local mechanic) He took it for a test run for about 3 or 4 miles. Said it worked fine and shifted really good. Got it to his house and parked it. He later tried to go out again but now reverse does not work and D acts like it wants to move but just sits there. When shifting to 3, 2, or 1 it dies immediately. I told him to check fluid level and he had to add 3 to 4 more quarts. Still won't move and had same symptoms above. Any ideas?

 

[clinebarger]

Check the shifter adjustment, Then pull it out, Tear it down & find out what went wrong. Installing a pressure gauge beforehand isn't a bad idea.
Did the "mechanic" not double check the fluid level??

 

[Lumpofcole]

Apparently they did not. My buddy did have to add much more. In regards to shift cable adjustment, I should mention he swapped his 4l60e to this 4l80e in a 2001 Gmc sierra 4x4. Is there any difference in shifter cables for this swap that your aware of Cline?

 

[clinebarger]

You can usually adjust the differences out with Long Shift Shaft Units, That's a very important step in ANY 60E to 80E trans swap!!

What was done far as tuning? Segment Swap?

 

[Lumpofcole]

I did a segment swap for him on hp tuners