Front diff nightmare. Please lend some advice.

So due to my mindset when it come to maintenance, which is "if I don't do it myself it's probly hasn't ever been done" I decided to change my front and rear gear dope. I used Lucas

$30 75w 90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w 90 full synthetic gear lube. The issue now is that my front diff is leaking pretty bad, like a puddle the size of an iPhone 5 every time I park my truck. I thought it might be the drain plug so last night I pulled it and added some RTV to both sides of the copper washer and refilled it with another $30 worth of Lucas. Which is still slowly leaking on my driveway. Any advice would be much appreciated. I drive my Tacoma almost 100 mile a day so i have to stop the leak. 1999 Tacoma 4x4 3.4

 

maybe get a new drain bolt and crush washer? I hope you didn't crack something by overtightening

 

Look like the leak is coming from the seal on the right...how about you go back to plain old 80W90 dino oil?

Howard

 

looks odd, but I would say washer. When I did my mine a couple of weeks ago, i re-used my washer with out issues. ...

 

The drain bolt and washer both seem to be in perfect shape. They both look brand new and I tried using some Lucas that was like 85w140 and it still leaked. I'm thinking I should replace the seals. Anyone know of where I can find a write up on how to do it?

 

Did you torque it down to spec?

 

Looks like the driver diff seal. Easy to replace. Just pull the axle pull the seal put in a new one and out axle back on. Prob bout 1hr of work.

The passenger side is a pain cause you can put the seal in too far. But the driver side has a stopper. Seals roughly $15 from the dealer and bout $5 if you have time to find it online.

 

I take it there was no leak before you changed the gear oil? Have you cleaned off the excess to determine exactly where the leak is coming from? Seems like the most likely candidate is the drain plug, if all you did was change fluid. I would clean everything up, check it in the morning to see where the leak originates from, then go get a new copper washer for the drain plug if that's what it is. I want to say the torque spec is 29 ft-lbs, too lazy to look it up right now.

 

Dont think its a drain plug leak. You can see that there is gear oil leaking from above the drain plug down.

 

If your truck wasn't leaking before you did the front diff flush, id say its something simple like your diff breather is stuck. You overfilled with fluid, and now when the diff warms up it creates pressure. The pressure can only escape through the axle seals.(instead of breather) Check the diff breather.

I hope this is the case. this would be a much easier and faster fix than replacing axle seals.

 

axle seal, and is possible that breather is clogged causing fluid to leak out of the axle seal or it just worn out and finally give on you.

 

Yea I'm going to try to install new bearing and seals and a new breather this weekend. Anyone have advice of the bearing? I'm doing them because I started hearing what I believe to be a bad bearing on the way home today, and I can grab the drivers side cv axle and it moves more than I think it should.

 

Was it a straight forward drain and fill? it shouldn't be leaking that much just because you put synthetic oil in there unless you had to pop the axle loose during your work. I know when putting my axles back in after my diff replacement, it all looked seated but had a few milimeters left to completely seal. leaked like yours.

 

No I just drained it and refilled it. It didn't leak until I gave the entire underside a purple power and pressure washer bath

 

Not sure if you resolved it, but looks that you swapped the fill plug to drain plug and vice-versa. Again not sure if it would matter.

 

You need the needle bearing puller from ECGS, in order to do the needle bearings. In which ECGS does not machine it properly to fit between the spider gear and needle bearing. It requires some "machining" in order to slip in between the 2. Your best bet is to find someone who has already done it for a first gen and use theirs. Mine took about 45 minutes to change.

 

Just replace the leaky seal and be done with it. Why replace perfectly good bearings (assuming you have no noise concerns)? You are only asking for trouble if a simple leaky pinion seal has you baffled. Remember this, oil leaks down. Not up.

 

He just said he has a noise....and He's not replacing the pinion bearing. It's the needle bearings that need to be replaced. And what does oil leaking down, not up have to do with anything?

 

i got my money on this^^

seal.

 

Yeah id say seal too ,but also check your breather, My rear has leaked in the past from the end when i forget to clean the breather.