Driveline vibration
#41
Sounds like Ford knew what they were doing when they used a 2-piece driveshaft. I have the suspension mods that are being blamed, but I have the stock driveshaft and no NVH or other problems. If it is a choice btwn suspension mods of proven value and the 1-piece driveshaft of unproven performance value I would go with the suspension mods. Maybe someone can make a lighter 2-piece driveshaft to address the weight issue??
#44
#45
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I just checked my pinion flange with a dial indicator and it looks like it is out of round by .040
not sure what the spec is but this seems like it is egg shaped enough to cause trouble at high speed.
not sure what the spec is but this seems like it is egg shaped enough to cause trouble at high speed.
#46
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Sounds like Ford knew what they were doing when they used a 2-piece driveshaft. I have the suspension mods that are being blamed, but I have the stock driveshaft and no NVH or other problems. If it is a choice btwn suspension mods of proven value and the 1-piece driveshaft of unproven performance value I would go with the suspension mods. Maybe someone can make a lighter 2-piece driveshaft to address the weight issue??
I wonder if the 2 piece drive shaft also allows for a looser spec on the pinion flange? This seems to be happening to people with both auto's and manual's but does it happen more to those who have changed the flange or used an adatper plate. This could also explain the aftermarket suspension theory, the more precise the suspenion gets the less play you have for a pinion flange being out of whack....made sense in my head anyways lol
#47
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Interesting ... I'm pretty sure I've put a dial indicator on the face of mine to check flatness ... not sure if I've done the outside to check roundness ... Will have to do that one day ... Since I have a V6 car with an 8.8 rear ... I bought the pinion flange new from a dealer on eBay ... it was the FRPP part ... not the factory replacement part ....
Last edited by dmhines; 6/1/08 at 09:02 AM.
#49
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For those that have replaced ... did you buy the FRPP flange or the factory replacement? And where exactly are you measuring the runout?
Last edited by dmhines; 6/1/08 at 12:06 PM.
#56
M any of you know i broke a driveshaft on a dyno run. speed was at 130 mph when the shaft let go. i replaced the shaft the next week, but have always had a vibration problem. i have replaced the exhaust, trans brackets, exhast hangers.. etc. I even swapped another driveshaft last week. How or who do i see about the flange runout. the shaft broke into 2 pieces when the caps came off the yolks. as the shaft broke the parts hit the fuel tank, exhaust and crushed the E-brake cable housing. see video for details. http://smg.photobucket.com/albums/v6...t=100_3932.flv
again how do check the flange for run out.
again how do check the flange for run out.
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I checked mine on the driveshaft. I agree that the outside diameter of the pinion flange does not make that much difference. Unless it is out a ton.
#60
I just chucked up a OEM pinion flange into our lathe. I chucked onto the seal surface of the flange and corrected the runnout so the face of the flange was reading .003. At the above red reference arrow it was reading .001 and at the above green reference arrow it was reading .001. I would guess with this flange installed onto a pinion shaft the readings would probably increase alittle but not by much. Hope this helps.