Rear diff fluid low, need advise
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Elder User
Joined: Aug 2006
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From: Mountaintop, PA
Rear diff fluid low, need advise
I have been getting a slight chatter when turning on an incline at really low speeds from the rear axle, so I check the fluid, it is low. (No leaks BTW) I need your advise before I go to Napa.
Should I top off with the L.S. modifier since I have the chatter?
or
Should I top of with the Syn gear oil?
Edit, Diff fluid was changed 20,000 ago and one recommended bottle 8 oz. (I think) of modifier was added during the change.
Should I top off with the L.S. modifier since I have the chatter?
or
Should I top of with the Syn gear oil?
Edit, Diff fluid was changed 20,000 ago and one recommended bottle 8 oz. (I think) of modifier was added during the change.
Hotshot
Joined: Feb 2007
Posts: 10,499
Likes: 10
From: Sterling Heights,Mi
WHat is "low" normally you pull th eplug, you stick your finger inthe hole, and the oil is 1/8" below.
If you are indeed low, you need to find out why!!!
Yes to the modifier, no to toping off with SYnthetic, replace with synthetic, then modifier, or buy the syn with modifyer in it
If you are indeed low, you need to find out why!!!
Yes to the modifier, no to toping off with SYnthetic, replace with synthetic, then modifier, or buy the syn with modifyer in it
Posting Guru
Joined: Dec 2004
Posts: 1,102
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From: Virginia - SW (Riner)
Diff Fluid
Yup, need to find out where its going or, if you're unlucky like me it was under-filled from the factory like our 2003 F350' rearend was. Luckily for us it didn't do any harm as we caught it early on (@ about 10K - I checked it) & it wasn't that low - (just a little less than a qt)
I now make it a habit whenever we get a new truck to check all the fluid levels prior to leaving the stealership. I know they are supposed to do it but the "delivery prep" folks aren't mechanics and usually only check the easy stuff - PS, Brake Fluid, Antifreeze & Trans.
DG
I now make it a habit whenever we get a new truck to check all the fluid levels prior to leaving the stealership. I know they are supposed to do it but the "delivery prep" folks aren't mechanics and usually only check the easy stuff - PS, Brake Fluid, Antifreeze & Trans.
DG
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Elder User
Joined: Aug 2006
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From: Mountaintop, PA
I think what happened was when I changed the diff fluid, I may have assumed that it was full when I spilled some putting it in. Plus it was winter and the diff oil was really cold wand when I checked to see if it was full the oil had not yet settled and leveled off in the case.
When I put the plug back in, I never checked it again after going for a drive. It is about 1/2-3/4" low. It is still golden brown, like it just came out of the bottle.
There is absolutely no leaks on the diff cover and the pinion seal is bone dry. This has been a very good truck to me! THis is a I can chalk up. Very cold gear oil +assumed was full= not full.
It is a 4x4.
When I put the plug back in, I never checked it again after going for a drive. It is about 1/2-3/4" low. It is still golden brown, like it just came out of the bottle.
There is absolutely no leaks on the diff cover and the pinion seal is bone dry. This has been a very good truck to me! THis is a I can chalk up. Very cold gear oil +assumed was full= not full.
It is a 4x4.
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Hotshot
Joined: Feb 2007
Posts: 10,499
Likes: 10
From: Sterling Heights,Mi
Then, I would just add the additive.. as far as the chatter, play with your hubs, see if it gets worse, or better by locking them in.
Good Luck Tim,
Good Luck Tim,
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Elder User
Joined: Aug 2006
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From: Mountaintop, PA
It was only 4.oz low. I thought it was lower than that. I asueezed 99.% of the 4 oz. bottle of friction modifier in it and it started overflowing. I ran the same route I always do and the chatter is gone.
I then tore into my shifter to see where it was leaking. It seemed to be coming out of the black boot that seals on the shifter. I found no tears and cleaned and reassembled. Then I checked my breather ontop of the tranny in front of the shifter. I could not spin it by hand, so I took a pair of pliers to it to free it up. I can now spin it. If it stills leaks, I am ordering a new breather. I think it is clogged forcing the oil out of the weekest seal in the tranny.
Then I cleaned my EBPV sensor tube. I bought everyhting new 2 years ago. I cannot believe how clogged it was just in that short period of time. Thats back together.
Truck needed alot of attention. It was a long winter.
I then tore into my shifter to see where it was leaking. It seemed to be coming out of the black boot that seals on the shifter. I found no tears and cleaned and reassembled. Then I checked my breather ontop of the tranny in front of the shifter. I could not spin it by hand, so I took a pair of pliers to it to free it up. I can now spin it. If it stills leaks, I am ordering a new breather. I think it is clogged forcing the oil out of the weekest seal in the tranny.
Then I cleaned my EBPV sensor tube. I bought everyhting new 2 years ago. I cannot believe how clogged it was just in that short period of time. Thats back together.
Truck needed alot of attention. It was a long winter.