i have a 2004 ford f150 fx4 that i just replaced the clutch pack in the rear about a month a go. now its shurding again when i start to turn left or right i added all the fluids that ford gave me and had a local shop fix it.I was told maybe change the fluids again to see if that helps.I also called southern gear and talked to them they told me not to put full senthict oil in that it can mess it up so any help would be nice havent owned the truck but a few months and had nothing but trouble with the rearend.

 

If the shop didn't put friction modifier then you need to put some in. Then find a parking lot that you can do some figure "8's".

Plus I think you are supposed to pre-soak the clutch pack before it is installed. I'd put the modifier in and try it out. Or take it back to the shop that did the work. But if they are telling you it needs the fluid changed this soon it sounds like they may not be the sharpest.

 

I'd stick with the synthetic that Ford recommends. If it is making noise when turning, add another bottle of friction modifier.

My 2000 9.75 traction lock started popping in turns at about 80k miles. I changed the fluid using motorcraft synthetic and had to add 2 bottles of FM to get it quiet. The 2000 TL clutches were shimmed too tight.

I just replaced an axle in my 2002 and had to change the fluid. I added Valvoline synthetic with one bottle of FM and the traction lock works great.

 

well i did add everything that ford gave me for the job plus one bottle of modifier.they did soak them for a while before they put it all togather and said it was tight.when the job was finished we took it out in parking lot and did figuer 8s was makeing noise while doing it then stops its been over a month and now its doing it again.but the ones that were in the truck before was burned up bad when i bought the truck. only thing i no do try is add another bottle or try and change fluids again and see whats going on inside

 

I bet adding another bottle of FM will do it. And I would not drive it in figure 8s with it popping. I think it is just causing unnecessary wear on the clutches.

 

I agree w/ Roadi, Add an bottle,give it sometime to break-in before doing hard turns.