Changing rear Diff oil
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From: So. La.
Changing rear Diff oil
I was thinking of changing the rear differential oil on my recently purchased '04, F150, 4x4, 3.73 LS, w/ 68,000 miles, and just thought I'd check with everyone to find out if there were any unique things that has to be done. Some for instances:
use a regular Ford diff cover gasket, and/or some gaskest sealer such as Right Stuff, any particular tightening pattern, and torque setting - or is snug + 1/2 turn okay. Any particular brand of 70w-140 oil - I was thinking of synthetic (runs cooler & lasts longer) and because when terrestic oil breaks down it tends to "gum".
I plan to tow a 28' TT - not more than several times per month, and a 22' offshore boat, about the same.
I figure the guy who owned it before me didn't do much of anything fluid wise and since he put 68,000 miles on it within 2 years, a diff oil change & Tranny oil change would be a good thing to do, as well as giving me a starting point from which to keep track of the fluid changes.
thanks,
use a regular Ford diff cover gasket, and/or some gaskest sealer such as Right Stuff, any particular tightening pattern, and torque setting - or is snug + 1/2 turn okay. Any particular brand of 70w-140 oil - I was thinking of synthetic (runs cooler & lasts longer) and because when terrestic oil breaks down it tends to "gum".
I plan to tow a 28' TT - not more than several times per month, and a 22' offshore boat, about the same.
I figure the guy who owned it before me didn't do much of anything fluid wise and since he put 68,000 miles on it within 2 years, a diff oil change & Tranny oil change would be a good thing to do, as well as giving me a starting point from which to keep track of the fluid changes.
thanks,
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Joined: May 2004
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From: Mirror, Alberta
As I recall the oil in there from the factory is synthetic so I wouldn't think of replacing it with anything else. I would check with a reputable dealer in your area to see if it really needs replacement as I think it is good for 100k if there are no water intrusion issues.
Not sure what kind of hitch weight you will have with those tows; take a look at my gallery to see how easy it is to exceed the GVWR. Not saying that it will be over, just something to pay attention to. These trucks weigh right around 6000 pounds without any extra load.
I guess the other thing to consider is why you would change the rear diff and not the front as well. Seems to me the recommended change interval is the same.
Not sure what kind of hitch weight you will have with those tows; take a look at my gallery to see how easy it is to exceed the GVWR. Not saying that it will be over, just something to pay attention to. These trucks weigh right around 6000 pounds without any extra load.
I guess the other thing to consider is why you would change the rear diff and not the front as well. Seems to me the recommended change interval is the same.
Last edited by bigdavewilson; Aug 20, 2006 at 05:40 PM.
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From: So. La.
I totally agree with you on "exceeding the GVWR" as this is normally the first rating that most people will exceed. That "tow rating" is a bad "rating" to go by and to use in conversation.
As for the front diff, the transfer case is part time so it only engages when the 4x4 system is "turned on", so it doesn't have the same "Loaded" mileage as the rear diff does.
As for the front diff, the transfer case is part time so it only engages when the 4x4 system is "turned on", so it doesn't have the same "Loaded" mileage as the rear diff does.
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From: Mirror, Alberta
Originally Posted by grey77
I totally agree with you on "exceeding the GVWR" as this is normally the first rating that most people will exceed. That "tow rating" is a bad "rating" to go by and to use in conversation.
As for the front diff, the transfer case is part time so it only engages when the 4x4 system is "turned on", so it doesn't have the same "Loaded" mileage as the rear diff does.
As for the front diff, the transfer case is part time so it only engages when the 4x4 system is "turned on", so it doesn't have the same "Loaded" mileage as the rear diff does.
Point well taken about the front diff.
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From: Fuquay Varina,NC
The rear diff shouldnt need changing if it has under 100,000 miles on it, Ford uses a high quality synthetic in there from the factory.
Even so, I changed mine out at 5000 miles anyway to AMSOIL, just for the hell of it. You will use regular RTV sealant to seal it back up. Ford does not show a bolt tightening pattern, but i usually just do every 4th bolt around in circles. Ford says to tighten to 33 ft/lbs
If you have a limited slip, be sure not to forget to add the friction modifier, or the LS unit will give you a hell of a time
Even so, I changed mine out at 5000 miles anyway to AMSOIL, just for the hell of it. You will use regular RTV sealant to seal it back up. Ford does not show a bolt tightening pattern, but i usually just do every 4th bolt around in circles. Ford says to tighten to 33 ft/lbs
If you have a limited slip, be sure not to forget to add the friction modifier, or the LS unit will give you a hell of a time
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Originally Posted by bigdavewilson
Not sure what kind of hitch weight you will have with those tows; take a look at my gallery to see how easy it is to exceed the GVWR. Not saying that it will be over, just something to pay attention to. These trucks weigh right around 6000 pounds without any extra load.
Now what you keep reminding us of is GVWR, thats just the truck and whats on it. making it a payload somewhere around 1600lbs-2600lbs depending on the truck. I've never heard anybody state they can haul 9000lbs in their truck. Here in Alabama you are good up to 8000lbs. It doesnt matter what Ford,Dodge,Chevy,Nissan, yada,yada,yada says. If you want to go over that you just buy a F1 tag. I'm sure that most places are the same and if you look on your tag receit you'll see 8000lbs. if you'll notice on this 1/2 trucks they'll say best "whatever" in its class, then to define class it'll be 8000lbs, rounded up to 10000lbs hence the 1/2ton. even though the highest GVWR that ford has right now in the 1/2 ton is 8200lbs, your over weight in Alabama on a regular tag.
Last edited by exiled; Aug 21, 2006 at 01:01 PM.
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speaking of the rear differential, mine was leaking, still under the extended warranty, and now I'm noticing a whiring sound from the rear. First thought it was the tires, but they have been rotated regularly and are wearing evenly. Could the whiring be coming from the rear differential if the dealership didn't put enough oil in it when they fixed the leak? I haven't found any leaks.
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Cargo Master
Joined: Jan 2005
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Originally Posted by grey77
I totally agree with you on "exceeding the GVWR" as this is normally the first rating that most people will exceed. That "tow rating" is a bad "rating" to go by and to use in conversation.
As for the front diff, the transfer case is part time so it only engages when the 4x4 system is "turned on", so it doesn't have the same "Loaded" mileage as the rear diff does.
As for the front diff, the transfer case is part time so it only engages when the 4x4 system is "turned on", so it doesn't have the same "Loaded" mileage as the rear diff does.
I think us that tows alot and yall that launch boat often changing the rear fluid is a good idea. for us tow'ers because of the workload we keep on the rearend, the boat lauchers well because of the water and backing up into it. i've watched some boat'ers get that rearend in the water pretty good. but of course i guess you have to if the ramp makes you or your boat drafts more water that what is on the ramp.
If the chunk is'nt leaking you can buy a pump for a parts store for around $10-$20, and just pump the fluid out. i change mine at 30000 and that how i do it. Never had a problem. I use the same pump to empty my brakefluid to replace it.
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From: Mirror, Alberta
Originally Posted by kpleasants
speaking of the rear differential, mine was leaking, still under the extended warranty, and now I'm noticing a whiring sound from the rear. First thought it was the tires, but they have been rotated regularly and are wearing evenly. Could the whiring be coming from the rear differential if the dealership didn't put enough oil in it when they fixed the leak? I haven't found any leaks.
Take the truck to a different dealer, one who will really diagnose the situation, and see what they have to say.
