Which gear lube for rear?

[bork]

Not much in "Larry's secrets". I wanted to add lube to rear since it it kinda low. what should go in ? & are they compatible? It seems I have a dana 60, full float, open, in a 1999. I got it with 250k. So I dont know any history of whats in it now. One of the pennz oil places wanted $180.00 to suck out & put in sythetic. They claim that is what is required. I'd rather buy at parts store & do myself for that price.

[u2slow]

Your owner's manual should spec exactly what Ford recommends.

IMO, since it not posi, I would fill it with Saftey-Kleen's 80W90 GL-5 that I buy by the 5gal bucket for $33. [img]/forums/images/%%GRAEMLIN_URL%%/wink.gif[/img]

[Mr_Roboto]

Ordinarily I'd say just top off with synthetic, but with the mileage you should do a full drain.

Pull off the rear cover and drain, then use paper towels to soak up what is in the bottom of the carrier (you will also get a little metal flakes in the bottom). I like to use some brake-kleen to make sure I get everything.

Use form-a-gasket to seal the cover back up. I like to snug the bolts, let the sealer set up some, then torque them fully. I feel this helps keep the sealer from going inside the pumpkin.

[MADVAN]

Bork
180.00 is insane!
If looking to save on some cash.
Check your gear ratio.
Required.
The dana 3.55 is dino.
The dana 4.10 is sythetic (required)

Bill

[bork]

Ratio is a 3.55. I'd like to pull cover & do it right like Roboto said , but for now,(due to timing & want enough time as not to rush job) if I did add dino & it happens to have syn, do think it'll hurt it? If the end seals are leaking, is there ever any visual evidence, besides braking? Also since Madvan says 3.55 gets dino, will it help in long run if I install syn, when I do the full clean out?

[Mr_Roboto]

I'd just top off with regular dyno.

[MADVAN]

Bork

You can upgrade to syn if you want. Just not required.
Remember if its an LS you need the additive.

Bill

[fordnut350]

If you need the syn, you can get Royal Purple for 9.99 a quart at Pep Boys. It also states the friction modifier is in it and not required.

[blageurt]

You only need synthetic if you don't want to change it often AND if you carry heavy loads (like me)or tow alot. Synthetic gear oil performs better under high heat /load conditions. If you are contaminated with water IE foamy emulsion, I would change it asap. I also have a 3:55 but it is a 70 FF. I have always used 80W90 dino because I change it often , like every 30000 kms. The only way to see if seals are leaking is to remove the drums. That in mind have all new brake parts ready so you only do it once like Forest Gump , you never know what you're gonna get.
Good luck.

[stroked_van]

In the Haynes I'm looking at right now........it states that the '99 model 60 uses 80W-90 QL lube. Same model 60 for '00 uses 75W-140 GL synthetic.
Would this make a difference if you have an early '99 vs. Late '99??

Also if you wanted to go with synthetic for the early '99, would you use an 80W-90 synthetic or 75W-140 synthetic?

[toalpi]

Ford and others say you can go 100,000 miles with 75W-140 syn. It is clearly worth spending a few extra dollars for the added protection. If I was north of the border I might go with a 75W-90 syn.

[stroked_van]

I will definitely go synthetic if possible. It doesn't bother me to spend the extra money. I just want to make sure of getting the correct weight and doing the job properly. [img]/forums/images/%%GRAEMLIN_URL%%/smile.gif[/img]

[clev]

Can/will someone comment on the "Slik-50" brand of gear lube?

[bork]

I think i have a bearing starting to go. noisey under deacceleration. I put in the cheap standard gear lube. The rearend driveline specialist in my area said ford had trouble with syn & went back to the standard stuff. I'm gonna have them rebuild & put in a limited slip at the same time. I'll probably go with the standard stuff again w/additive.

[toalpi]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bork</div><div class="ubbcode-body"> The rearend driveline specialist in my area said ford had trouble with syn & went back to the standard stuff.</div></div> What trouble ,when trouble, and when changed? Not buying any of what he said.