Installed new flexplate, now worse with loud rattle...

[Shawn]

On my M1008 I was getting the occasional grind with the starter. Finally replaced the flex plate. Not a fun job pulling the transmission/tcase but got it buttoned back up. Now I get a horrible rattle sound.

Flexplate I got:

https://www.oreillyauto.com/detail/c/pioneer-inc/pioneer-inc-flexplate/pio0/fra142/v/a/4094/automotive-truck-1986-gmc-k3500-pickup-4wd

6.2 diesel, TH400 trans. I made sure to properly torque the bolts. Tried to make sure there is only 1/8" gap between the flexplate and torque converter. It had about .25" before. Now its worse with spacers. FML

Anyone had this issue?

View attachment flexplate.mp4

 

[Shawn]

Never mind... think I found the issue. The damn flexplate weight is hitting the starter housing. Pioneer flexplates suck!

 

[sweetk30]

Pull starter . Clearance that area and re install .

Had a cluch fork hit pressure plate . . . Mech fork on hydro = no good combo . Had to pull and redo all over .

 

[Shawn]

@sweetk30 - Thanks! I didn't even need to pull the starter. Just used a long blade on my Milwaukee sawzall and clearanced the starter that way. BAM! Fixed.

Ticks me off their tolerances on that weight is WAY off compared to the old flexplate.

 

[Shawn]

Now I'm getting a vibration in 3rd. Looks like I may take out the spacers that I recently added. FP to converter is 1/8" but it was almost 1/4" before. I wouldn't think that would cause vibration.

 

[Fastereddie]

Now I'm getting a vibration in 3rd. Looks like I may take out the spacers that I recently added. FP to converter is 1/8" but it was almost 1/4" before. I wouldn't think that would cause vibration.

If the weight was bad enough to rub, it makes me think the damn thing Isn’t even balanced correctly

 

[Shawn]

If the weight was bad enough to rub, it makes me think the damn thing Isn’t even balanced correctly

I compared it to the old one and it looked exactly the same but that weight could be thicker I guess. I would think vibration would happen with rpm but its fine at high rpm in neutral and 1st and 2nd. My guess is when the weight got welded, there was an air gap.