Thicker diff oil (to slow leaks)

[78Suburban]

alright, here's the deal. my diff leaks.

I'm gonna get a tube of the right stuff, can of brake cleaner, and a couple of quarts of diff oil (I wish I knew how much a 14bff and front 10 took)..
Any way, the heat of summer is pretty much over, and winter is soon to come. The coldest it might get is 20*.... would that be too cold for a heavier weight gear oil? I'm thinking of getting a thicker oil to slow down the leak.. What's thicker than 80w90?? Or should I just try to stop the leak (which I really don't think I have the sill to do) ....

 

[pauly383]

Just get what matches your areas temperature range . And fill each one until the fluid comes back out the fill hole .

I run Redline heavy shockproof with my locker , but run 85 140 in my front , but I am in AZ , we may see freezing some nights , but usually not .

 

[blasterD]

The last time I changed the fluid in my 14bff it held 4 quarts. I have never owned a 10b, but my d44 held 2.5 quarts. Hope this helps.

 

[4xcrazy]

listen, NOOB,,, , it's not considered a leak, unless you can actually see a drop of oil getting ready to drop off the diff,,,,nothing is a leak withough this proof,,,,,


hell, mine leaves a trail behind me

 

[prossett]

I also regularly use 140 weight gear oil in the diffs, and gear box. The 90 stuff froths up real quick at high temperatures.

 

[Brocky]

listen, NOOB,,, , it's not considered a leak, unless you can actually see a drop of oil getting ready to drop off the diff,,,,nothing is a leak withough this proof,,,,,


hell, mine leaves a trail behind me

Hehe I said it before, my rig leaks like a teabag.

 

[diesel4me]

Try...

I used 85/140 gear oil in my leaky transfer cases and rear ends..and I live where it gets pretty cold sometimes..below zero a bit once or twice in the winter..I never had any trouble..now if I was able to get Straight 140W oil... --that would have been a different story!..

I have also added STP "Gear Oil Treatment" it comes in a tube like toothpaste!
OR "Motor Medic"or "Lucas Gear Oil Treatment"..they all slow leakage and help reduce friction and wear..one old timer I know puts about half a grease gun full of chassis grease in his rear axle that leaked at the pinion seal,then topped it off with gear oil!--he claimed it wouldn't hurt anything,and swore it worked,so I tried it on a leaky front axle I had in one vehicle..

I did the same on my leaky "Closed" U-joint 69 dana 44 axle I had under my 72 Chevelle wagon,it had a U-joint that was in a closed in hub that swam in gear oil,and it had leaky felt "wiper" seals that I didn't feel like changing,since it took all summer for the 90W to leak out--it made a mess of the driveway more than it was a serious problem ..it worked rather well,I just pumped in some grease,and topped it off with gear lube..it didn't stain my driveway anymore!

BTW,your leak doesn't look that bad...I've had a few trucks I had to fill the diff every week,or sooner if I went on a long ride of 100 miles or more,until I fixed the pinion seal!...

 

[78Suburban]

so my gears aren't gonna shatter if I run 85 w 140 in 20 degree weather?
I'm just making sure that's what yall are saying, cause I don't want to mess up my pride and joy.

 

[BSav]

Thicker diff oil

I run Lucas diff oil in both of my 10 bolts front and rear. They hold about 2 quarts each. I split it 50/50. 50 regular 90 weight and 50 Lucas. Where I live in the summer it can get to over 100 and the winter can creap to about 10 below. I have run it that way for a few years now with no problem.

 

[jhellwig]

Being the farmer that I am I have come across a good fix for leaky gear boxes. I am fairly sure this trick will work in a differential also and If I ever needed to do A quick fix I would do it:


I have a brush mower that has a ripped up seal in the bottom of it. I just go to the local machinery dealer and get some corn head greese. It isn't as thick as regular grease and will melt and flow into bearings and such. It takes a while for it to all seap out. I fill the gear box chuck full of it. Works like a charm. And when the gear box cools down some after use you don't have to wory about it leaking oil everywhere.



Oh yeah I ofrgot an idea. YOu could just stop being lazy and replace the seal.

 

[78Suburban]

YOu could just stop being lazy and replace the seal.

If someone will lay it out for me in highly detailed instructions, I will be glad to.

 

[350k5]

This won't be detailed but here is the basic idea... at least for a 10 bolt. 14bff I'm sure its different but here is the general idea to let you know if you are willing to do it or not.

Looks like the pinion seal needs to be replaced. To do that you've got to remove the Pinion bolt... better have a big breaker bar or an impact (300ft/lbs) to get it off. Once you do that just replace the seal and bolt the nut back on. Careful not to over tighten, on used bearings you want it to be around 6-8 inch pounds (10 Bolt again don't take my word for that). You are supposed to also replace the crush sleeve but I hear most guys generally do not. To each his own.

Again that's what you do for a 10 bolt... so there could be a lot of differences between that and a 14bff. I'm not sure thought but that's better than nothing... at least until someone else who knows for sure comes along.