Flexplate/Crank Mismatch
 

This is like Deja vu all over again:|

Today was supposed to be the day things got moving, but then when trying to install the flexplate on my motor i realized today was the day of confusion and stress.

As you can see in the pic, the flexplate i got does not match up with the bolt pattern of the crank.

https://farm5.staticflickr.com/4384/...ae4b2563_z.jpg

Assuming the empty hole matches up with the dowel on the crank, i have flipped the flexplate both ways, and they still dont match up. Not the flipped it would change the bolt pattern but whatever.

Thinking maybe i just got a miss pick plate, i headed to a different parts store and grabbed one. Same exact issue. What really are the chances that 2 flex plates, from 2 different places, are both miss picked?

The block it self is 100% a gen 3 due to the cam sensor being located at the rear top of the block, along with the marking 12560625 on the block itself at the rear driver side should render it a 5.7.

Anyone ever run into anything like this? in my previous car i had to run a silverado SS flexplate due to the spacing, but im 98% the bolt pattern between the 6.0 and the ls1 flexplate were identical.

I haven't found much but this should not be a problem. Either you had double the bad luck or you have mystery crank.....

https://ls1tech.com/forums/attachmen...-motor-cc5.jpg

Grab your calipers/kirk and measure the bolt circle diameter. Should be 3.11" center to center. Check the flexplate and check the crank best you can. Let me know what you come up with.

Could be a bad run, and both brands use the same manufacture. I had a flywheel like this back when I built my 86.

Below is what I got back from running the VIN before i purcgased in 2008/2009... No mention of crank and I didn't touch it during my tenure either

No solid info yet due to not having a caliper, going to have to borrow my techs again.

But I have read after digging threw google that Napa/autozone/Orielly list the correct part number as "FRA159" for 98-02 60e LS fbodys, but that is an error and should list "FRA471" as the correct one. So hopefully that is it.

Looks like i got 2 fubared flexplates

Time to play the lotto

Since there is 6 bolts they should be equally spaced, no?

Heres what i found.

https://farm5.staticflickr.com/4509/...d555ac54_z.jpg

No, measure across bolt center to bolt center.

While that is correct, this still gets the point across that the plate is FUBAR'ed

Each hole is .466 Diameter, inside edge to inside edge of hole is 2.549.

by my most likely wrong calculation, that puts it at 3.015" center to center.

Even still being pretty close to what you posted, if the holes are spaced out correctly, but are "warped" or twisted out of skew like i think i mine are, i will have the problem im having.

Here is the second flexplate

https://farm5.staticflickr.com/4394/...3ba36c9f_z.jpg

Hole Diameter: .466
Inside Edge to Inside Edge: 2.538
center to center: 3.004

Who makes the flexplate? For reference, when ordering end links for my parents yukon denali, rockauto sent me outer tie rods for an entirely different car despite the acdelco box stating the correct part number and pic on rockauto showing exactly what I needed. When I sent it back, they sent the same thing again. Turns out acdelco misboxe that part number. I bought stuff at AAP so I could verify the right part. It's possible you could have the same issue and both rockauto and NAPA got misboxed parts.

Didnt snag a real pic, but stopped home at lunch and measured the space between the bolts on the crank.

An equal 1.200" between each. Perfectly symetrical.

https://farm5.staticflickr.com/4431/...2ac89dba_z.jpg

Pioneer is the manufacture of the plate, and i think they supply to both napa and autozone, which is were i got the plates

I guess its time to get one from TCI

Currently waiting on a replacement one from napa. I deal with the local napa a lot since we buy a lot of parts for the used cars we get traded in threw them, so i like to give em a chance to fix it. If the one i get is wrong again, a TCI one will be ordered

so no fancy SFI-rated part?

not yet, hopefully.


Hoping the Napa one shows up and is good to go. Save me some money and down time. Im itching to get this thing in.

:rofl::rofl:

What!

Rockauto lists both numbers for the flexplate.

For some reason, I thought the holes were supposed to have random offsets like you are seeing. That thing is fuuuuuuucked :rofl:

Nah son, random holes would make that thing less balanced than kohlers body after his juice cycles.