My 2000 F150Supercab 4x4 has 75-140 full synthetic and it is supposed to be lifetime lubrication. The front uses standard grease and is supposed to be changed at some point, every 3k if used in severe service. The owners manual says if you use full synthetic in the front diff in severe service you don't have to change it every 3k. Non-severe service the service chart doesn't mention the front diff fluid change until 150k. Go figure.

 

I had the same problem with my 2000 F150 4X4. I did purchase the friction modifier. It was not an immediate fix as I thought it would have been. It was every bit of 750 miles before I noticed the shimmering was gone. I bought the product at Advance Auto Parts in Indpls. The cost was $4.50 for a 7 oz. bottle.

DaWG

 

It has been three weeks since the "new super grease" was added to the rear end. There has been absolutely no change! I still get a tremor when starting from a dead stop. The problem is even more defined when pulling a trailer.

 

Fritterboy

Did you put the "super greese"(SG) in the diff. or did the dealership do it? If you did not then how do you know that they actually applied the "SG"? I would change out the fluid and use the friction modifier. That way you know with certainty that it was done. A little additional expense, but it may be worth it.

I pull a boat as well, and I am awaiting the season to see if the friction modifier helps with that as well.

Good luck

DawG

 

I have a nearly brand new '04 F150 2wd with a 3.55 LS differential that has started to do the same thing (rear end shudder) when cold. It does it once or twice in the morning in first gear coming out of stops with the wheels turned. It doesn't shudder under the same conditions in the evening after sitting out in 60 °F conditions for 10 hours. I will take it in next week and have the dealer check it out, but it sounds like this is a common enough problem with Ford LS differentials that they would have solved it by now. I have a hard time believing it came out of the factory without the friction modifier, but...

 

Joe

I took mine in to have the pinion seal replaced and as a result I got new fluid, that is when mine started.

Good luck on your truck.

DaWG of Indpls

 

Joe

I took mine in to have the pinion seal replaced and as a result I got new fluid, that is when mine started.

Good luck on your truck.

DaWG of Indpls

 

I just replaced my diff fluid again when I found out I had a leaking axle seal. I had to pull the axle to replace the seal. This time I put in two 4 oz. bottles of modifier at the recommendation of the Ford dealer's parts guys. It is better than it has been in a while. I don't feel the chattering that much any more.

Like I posted before, there is a TSB out on this subject. I don't know if it covers the 2004 model, but the fix is to replace the clutch pack and remove 0.10" worth of shims. I also posted the TSB on this site.

 

I took my '04 F150 2wd with a 3.55 LS diff into the dealer and they put in a "clutch pack" after I complained about a shudder coming out of 1st from a stop with the wheels turned. It seems to have worked for now. No more shudder.

 

I have a 1997 with 3:55LS and a 5 speed tranny.Mine also does the "chatter" when taking off.I thought it was the clutch, but it only does it when it is cold out and untill the fluid gets warm ... I am running Royal Purple fluid, I am going to pick up a bottle of the friction modifier and see what happens.

 

I have the same shutter mentioned in my 2004 fx4 when taking off from a dead stop when cold. My dealer said he couldn't find anything wrong, but my 2001 lariet 4x4 didn't do that.

 

I have the same thing in my expy. I changed the oil out and added modifier. This helped but it is back!!! I thought the added power I have in the motor added to the problem but it seems stock trucks are having the same prob. How much is a new clutch pack?

 

I can't seem to find the TSB Roadie posted here. Any chance anybody could link to it or post the TSB #?

I'm getting ready to take mine to the dealership for this, and i'd really like to be armed with the TSB.

Thanks, -JZ

 

Clutch pack kits are 88.00 from stealership but you need FORD service tools in order to install it, they got you by the grapes!!!

 

Screw that - truck only has 12,000 miles. It's done it since about 8,000. They're gonna fix it for free! That's why i want the TSB...