Topic Sponsor
2004 - 2008 Ford F150 General discussion on the 2004 - 2008 Ford F150 truck.

to replace front diff oil...

Thread Tools
 
Search this Thread
 
Old 06-25-2010, 07:40 PM
  #1  
Senior Member
Thread Starter
 
bloodvette's Avatar
 
Join Date: Dec 2009
Location: Winnipeg, MB, Canada
Posts: 156
Likes: 0
Received 0 Likes on 0 Posts

Default to replace front diff oil...

I have a slight leak on my front diff cover so being at 95,000 miles I'm taking this opportunity to replace the oil with a synthetic 75W-90 which I picked up this afternoon. (and 4oz friction modifier)

a couple questions:

Can i just drive the front up on ramps or should I jack both sides by the frame so the front axle hangs lower? or is there enough room to get at the cover on ramps. I know there is a plastic shroud that almost butts up to the front diff which can easily be removed. I had it off to change my power steering pressure line a few weeks ago.

Is it true that the front diff (which is always the 8.8" in all models) is always an open diff and they're never a limited slip? and If so why is the limited slip friction modifier required? (my manual says to use a 4oz bottle with a fluid change). I WILL use it, I'm just wondering.

I did my rear axle pinion seal myself a few days ago and when putting in new 75W-140 (with friction modifier), it was easy to squeeze the bottle's nozzle into the fill port to fill the diff. Can this be done on the front diff, or is it so tight in there that I'd need a hand pump to get the oil in? The oil I'm using is the synthetic quaker state with the pointy nozzle.

Thanks,
john

Last edited by bloodvette; 06-25-2010 at 07:43 PM.
Old 06-25-2010, 08:50 PM
  #2  
Something
 
xJimbos's Avatar
 
Join Date: Sep 2009
Location: Sussex Co. Delaware
Posts: 215
Likes: 0
Received 1 Like on 1 Post
Wink

You don't need the friction modifier on the front. It is not LS and does not require the modifier. The instructions from Ford and others on this is quite confusing because of how it is written. Now, I know of people using the modifier on a non-LS (and I would like to hear someone chime in on an actual reason to use the modifier on a non-LS as I have not really read any real good answer to that question besides "it reduces friction;" Ford doesn't say to use it). The modifier reduces friction on the clutches within a LS diff. but the oil itself reduces friction on the metal gears themselves, which is all there is on a non-LS diff.
As far as getting to the thing and refilling the diff., on my 5.4 I can crawl underneath and have enough room to remove the cover plate and then refill the thing; no ramps or jackstands needed. Now I may be wrong with this but: the front diff. does not seem to move on my truck. It is bolted to the frame using brackets. Each wheel moves up and down on the suspension, but the axle is straight and the CV-joints at the ends of the axle are what moves up and down and turny turny.

I read in a number of different places that the front diff. is supposed to have a fill hole and a drain hole. Not on mine. I got to remove the cover and throw a new gasket on there to get the old fluid out, but there is enough room to squirt new oil into it if you get those slim, tall containers of gear oil with the squirty nozzle.
Old 06-25-2010, 10:39 PM
  #3  
Senior Member
 
ford4wd08's Avatar
 
Join Date: Feb 2009
Location: Alcoa, Tennessee
Posts: 3,138
Likes: 0
Received 50 Likes on 46 Posts

Default

ramps would be easiest. jacking it up wont give an advantage, because like stated it is attached to the truck in the frame, the flex in the front suspension comes from the cv's and the struts the axle itself doesnt move.
Old 06-26-2010, 02:07 PM
  #4  
Senior Member
Thread Starter
 
bloodvette's Avatar
 
Join Date: Dec 2009
Location: Winnipeg, MB, Canada
Posts: 156
Likes: 0
Received 0 Likes on 0 Posts

Default

ok thanks guys. yea it's not a solid front axle, brain fart. Unfortunately a drain and refill won't work in my case becuase it's my cover gasket that needs replacing. BUT, if I do spot a drain plug when I'm in there, I'll report it here. Thanks!
john
Old 06-27-2010, 12:02 AM
  #5  
Senior Member
Thread Starter
 
bloodvette's Avatar
 
Join Date: Dec 2009
Location: Winnipeg, MB, Canada
Posts: 156
Likes: 0
Received 0 Likes on 0 Posts

Default

it is done. Drove up on rams, (glad I did), removed the plastic shroud I mentioned earlier, took the cover off, sprayed some brake cleaner to get all the old dirty oil out- which was low, and quite dirty. didn't seem like a full 2L came out, but it made me feel much better to see SOME oil come out considering there was a leak. The bolts on the cover weren't too bad to access. The upper 3 can be accessed with a long extension and going over the frame brace, the others just with a short 12mm socket on the 3/8s rachet. Blue gasket silicone on the cover, smeared it with the finger. Put in and tightened the bolts and gave the sealant 1/2 hour to set. To fill, I could not hold the bottle at a good angle so I cut a piece of hose that fit snug over the pointy nozzle and just squeezed the bottle with the other end of the hose in the fill hole. I did half a bottle, then put the friction modifier in the bottle and finished off that bottle, and then added in the other bottle until it started to flow out of the hole. Done. I'm almost at the 100,000 mile mark now so I'm changing all the fluids. Both diffs are done. next is the tranny 13.2L and transfer case 2L.

john

edit: I confirmed the differential is an open differential and that there is no drain plug.

Last edited by bloodvette; 06-27-2010 at 12:06 AM.
Old 01-31-2016, 04:58 PM
  #6  
Junior Member
 
Troyb36's Avatar
 
Join Date: Dec 2015
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default Where to put fluid in at?

Where did you put the fluid in at?
Originally Posted by xJimbos
You don't need the friction modifier on the front. It is not LS and does not require the modifier. The instructions from Ford and others on this is quite confusing because of how it is written. Now, I know of people using the modifier on a non-LS (and I would like to hear someone chime in on an actual reason to use the modifier on a non-LS as I have not really read any real good answer to that question besides "it reduces friction;" Ford doesn't say to use it). The modifier reduces friction on the clutches within a LS diff. but the oil itself reduces friction on the metal gears themselves, which is all there is on a non-LS diff.
As far as getting to the thing and refilling the diff., on my 5.4 I can crawl underneath and have enough room to remove the cover plate and then refill the thing; no ramps or jackstands needed. Now I may be wrong with this but: the front diff. does not seem to move on my truck. It is bolted to the frame using brackets. Each wheel moves up and down on the suspension, but the axle is straight and the CV-joints at the ends of the axle are what moves up and down and turny turny.

I read in a number of different places that the front diff. is supposed to have a fill hole and a drain hole. Not on mine. I got to remove the cover and throw a new gasket on there to get the old fluid out, but there is enough room to squirt new oil into it if you get those slim, tall containers of gear oil with the squirty nozzle.
Old 01-31-2016, 06:17 PM
  #7  
Senior Member
 
Tommy J's Avatar
 
Join Date: Dec 2012
Posts: 935
Received 83 Likes on 69 Posts

Default

I think he was saying he thought it had both but without a doubt it has a fill hole. He had to squirt the new oil in somewhere right



Quick Reply: to replace front diff oil...



All times are GMT -4. The time now is 12:08 AM.