Hello everyone!

Just posted a how-to for changing your rear axle fluid here: http://members.shaw.ca/pferlow/f150_diff_oil.htm

If you haven't done so yet I would highly recommend it. I have 90,000kms on my 98' and the oil that came out of my 3.55LS was black as black can be and dirty!

I used Redline 75W90 100% Synthetic @ $13CDN/quart from www.mopacauto.com . No friction modifier required.

Total cost about $65CDN with a new gasket & silicone sealer.

Ya... I know, it's not 70W140 but some ford tech's say 70W140 ford stuff doesn't absorb water and leads to ruined axles.

 

Thanks for all the information. I am going to use 75W90 Mobil synthetic oil. Whats the deal with friction modifiers, do I have to add anything?

 

Good job, Peter

 

Peter - Thanks for the tips! It was a no-brainer following your procedure.


GB1277 - I used the 75W90 Mobil synthetic. Good stuff! Smells like hell, but good stuff.

 

Air Assault, how long have you lived in new milford?

 

DrDevon - I've been here since 97, moved up from Danbury. You know this place?

 

....I lived there for five years as a kid. Really loved the town - even the (nearly) yearly flooding of the Housatonic. Lived on Meetinghouse Terrace, went to Pettibone, Schaghticoke (sp.?) and New Milford High before moving out. Plenty of fond memories fishing the East and West Aspetuck river, running, sledding and playing football with a lot of the kids that lived on Danvers road.

What brought you there?

 

DrDevon - I lived in Danbury most of my life. I got married, had a son and Danbury just wasn't cuttin' it to raise a family in. Moved a whole 18 miles up into the little hamlet of New Milford. We love it here, a really great town!! In fact, if you get alittle home sick - part of the Adam Sandler movie "Mr. Deeds" was filmed on Bank Street, off of the "Green". You want to talk about wild, they filmed last summer and the shots were supposed to be in the winter in New Hampshire. They made snow (I'm talkin snowball makin snow) on Bank Street and covered the entire road and sidewalks. It was quite a sight!! How did you get to Houston?

 

....moved to St. Louis, went to U. of Missouri, went to grad school at Texas A&M, moved to Fort Worth, and then to Houston. That's about 15 years, though, all told. People are amazed when I tell them to take a vacation in New England...."gee, isn't it crowded up there?" Just shows where they haven't been. Gorgeous around there; could pick quarts of blackberries and raspberries down toward the banks of the river, and just amazing wildlife and woods, all told. Real small town charm - glad you could treat your family to it.

Rocky Berry owned that Bank Street Theatre when I was a kid and talked to the kids at school every year about being in business. I hope he's still able to be independent, although one would doubt it. Will have to see that Sandler movie just to see the old place - thanks for the tip.

What do you do in that part of the world?

 

p_ferlow:

Those are great instructions thank you very much for the information. I asked this question in another forum but I will go a head and ask here as well. I thought the rear def. was a life time lube unless submerged in water. How often would you recommend changing the fluid? From your instrutions I can see the lube is NOT lifetime . God I love these forums I learn more every day. Again thanks for the excellent instructions.

 

Nothing is lifetime! I would change out every 30k. That is if you plan on keeping your truck very long.

 

Yup, I'd agree. I don't know where the manufacturers come up with "lifetime lube".

Mind you there are no hydrocarbons from combustion to pollute rear axle oil like there is in the motor but you still have friction material in the LS diff adding to the oil as a fine powder and those gears are metal on metal so things do wear out and this goes into the oil.

I would change it every couple of years myself, more if you do a lot of driving or towing. It's cheap insurance.

I'll be doing a how-to on installing CHEAP sound dampening material soon. Click here to see the start of my article.

 

F-150 BassLow & p_ferlow:

Thanks for the information. I must admit I have never changed any lube in the diff. before in any car or truck I have owned. Of course this was before I started visiting F150online.com. I "use" to be with some things including the rear diff. "not going to touch it, not going where I haven't been before and screwing it up" but with all the great information here from alot of people with alot of knowledge it's like I can't wait to try some of this. I already have at home in a folder the instruction I printed out that p_ferlow wrote in the begining of this thread. With new trucks I use to be the type that would take it to the dealer for anything like plugs, wires, etc. with the exception of oil changes. Not anymore with these forums and the information I'll be doing ALOT more things myself Thanks again...

 

Nice article and information. I will be changing my gear lube with the next oil change. Thanks again for the information.

 

Great site -- first posting .

Yesterday was the first time rI ever changed rear axle oil. It went well (nasty, stinky stuff). I used a gasket (man, is that thing thin) in combination with soime black RTV gasket funk. I let is set up a day before driving it just to be safe (maybe overkill). No leaks. The pain in the rump was getting my head/neck crooked up next to the differential so I could see the actual fluid level in the filler hole.