4L60E and 4L80E flexplates

[rlsllc]

I read somewhere (and can't re-find it) that the 4L80E and 4L60E use a different flexplate. I am assuming that the 3500 series van that my VIN R 5.7 engine came from had a 4L80E, but don't know for sure.

I can't seem to find info on what interchanges, whether I can use the flexplate off of my 1999 4.3 on the 5.7, or what I need to buy to hook the 1999 5.7 to the 4L60E in the 1999 Safari.

I'm having the trans rebuilt and updated, maybe I'll ask the trans guy.

Any Ideas????

[rlsllc]

I can't remember anything I do, apparently.

I just took a 700r4 out of a van, and so I went and grabbed the flex plate, and sure enough, the TC bolt pattern is about 1/2" smaller. It is a flex plate that was on a 1988 or so 305. It 'looks' like it has the same bolt pattern on the crank circle and counter weight as the one from the 1999 5.7L.

For the $60 a new one will be, I think I'll just buy one. After all, if my used one is bad, they are a pain to change. Question now is, for what application should I buy it for? Rock Auto only shows one for Express vans, so do all Express vans have a 4L80? I have a hard time thinking that the 4L60E wasn't used in the lighter duty ones, but who knows. They don't list one for the 1999 Astro/Safari, so I couldn't cross referance.

:-k

[Mr_Roboto]

You should b e able to check pretty easily I think, but 3500s should be 80s I believe. You have the right idea getting a 5.7 flex plate. My 80E came with a 454 flex plate, sucky thing is it's externally balanced.

[MountainManJoe]

holy post revival batman.

[WoodButcher]

Never let it be said that a question goes unanswered around here, all good things come to those who wait!

[sfeaver]

4.3 flexplate will work.. Same as 5.7 for the 4L60E.

[Mr_Roboto]

Hrrm, trying to think if I have a HD flexplate in mine or not. I know that I have 2 distinct bolt patterns on it, and that the 80E takes the wider of the 2. Since I have the dual pattern flex plate it does seem to bolt up.