2004 rear problems
poopin.....on this thread
Joined: Sep 2010
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You wont regret spending a few bucks on this. I put in Mobil1 in the rear end and 2 bottles of friction mod in.
here is the friction mod the dealer told me to use.
http://www.summitracing.com/parts/FMS-M-19546-A1
Senior Member
Joined: Nov 2007
Posts: 557
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From: NYC
You wont regret spending a few bucks on this. I put in Mobil1 in the rear end and 2 bottles of friction mod in.
here is the friction mod the dealer told me to use.
http://www.summitracing.com/parts/FMS-M-19546-A1
here is the friction mod the dealer told me to use.
http://www.summitracing.com/parts/FMS-M-19546-A1
poopin.....on this thread
Joined: Sep 2010
Posts: 1,008
Likes: 33
i used 75w90. because i dont do a ton of towning. however if youre doing alot of towing you probably should use the 140. also when you drain your fluid that is in there, make sure you pick up a cheap-o screen to see if there are any noticeable metal flakes in the oil. i had an old funnel that we used for race fuel that i ran the fluid through before it went into a 5 gal bucket. it was a very fine screen and i had a little bit of metal dust but for a truck with 65k on it....not bad at all.
Last edited by rubbinsracin; Mar 9, 2011 at 11:49 AM.
Thread Starter
TJ_04F150
Joined: Mar 2011
Posts: 19
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From: Allentown
I had the same problem. i have an 04 with the limited ship and i had my rearend making some grinding and funny noises on slow turns and from a stop. i went and drained the fluid. no materials or anything in it because they ran it through a strainer. when they filled it back up they put in 2 bottles of friction modifier then filled the rest up with synthetic diff fluid. made all the difference in the world. saw my mileage go up about a half MPG with the modifier and synthetic fluids.
poopin.....on this thread
Joined: Sep 2010
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lol. from what i know these rear ends are good as long as you give the the proper attention they need. my rearend was replaced right at 60k before the warranty went out on it and they didnt put that modifier in and after i put new fluid and the modifier in it, its been like brand new. 8k miles later.
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Joined: Feb 2011
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Originally Posted by TJ_04F150
You know this from experience? Youve had this problem in your truck?
Performance Driveline opened it up and changed the lube..I dont think he added any friction modifier. I'll try it for a temp fix but I dont know how the rears going to hold out. I think I'm going to shop for an 06-08 rear.