2002, F-250, 7.3 diesel. Last fall started shuddering when turning. Took to local Ford dealership (good one). Determined shudder was coming from rear end. Replaced some bearings. Shudder completely disappeared. Has been fine until early this month started to shudder exactly like last fall. Took back to dealership. They determined needed new rear end clutch plates. Removed old plates, that didn't look bad according to mechanic, but the plates were not Ford parts. Service manager ordered 2 types of Ford clutch plates and non matched. Purchased pickup Oct. 2017. No history available. The service manager and I suspect the rear end had been worked on by previous owner(s). Any suggestions in determining who made the old clutch plates? Ford service manager is contacting Jaegar service rep to see if he/she has any suggestions in determining the origin of the odd clutch plates.

 

Ford had a special additive that needed to be add to limited slip differentials . Without this additive the rear would shudder/chatter on turns. Check with a few parts stores , you should be able to obtain the additive. It was only a few ounces that got added to the differential lube.

 

If you have it apart, why not just add OEM clutch packs to both sides, some fresh lube and friction modifier and button it up. I normally soak the new friction plates in gear lube for 24 hours before installing. I also install them with a higher than normal pre-load for better operation. Then go do a few slow figure 8's in the dirt to get the friction modifier worked into the clutch packs. Most LS's don't work for crap from the factory because folks used to complain about noise from the rear (groaning) when turning. Because of this, Ford started setting them up from the factory with a light pre-load making them virtually useless, but the Customer is happy because "I have a Limited SLIP" axle.

 

Thanks for the info. I spoke to the Ford service manager and mechanic yesterday. The clutch packs in my pickup's rear end are very different from the standard factory Ford packs. The clutch rings have 4 ears rather than two (std), and the spacers and disks are backwards regarding which is splined and not splined. If I remember correctly the packs in my pickup have splines on the spacers and none on the disks while the Ford replacements are just the opposite. The existing packs also have a 4-corner spring set up which is different from the factory replacement. Over last weekend, the service tech soaked the packs in a friction solution, reinstalled them (because I needed my pickup), and so far no shuddering when turning slowly. I have much hauling to do over the next week so we'll see if the shuddering resumes. Again, thanks for your response. R

 

I just noticed you purchased your Fords through Towne Ford. Interestingly, the dealership with whom I've been working is Town Ford/Lincoln, East Wenatchee, WA.

 

Cool...My Town Ford/Lincoln is located in Orchard Park, NY.