Toyomo

I got an 89' 4runner, and I noticed just a few days ago that the rear of the car was very noisy. Best way I can describe the sound is that it sounds like a train running on tracks pretty much. I took a quick look under the car and it was an...absolute mess. There was oil kicked up all over the tires and underside of the car, after a quick sniff I determined that it was gear oil.

I also noticed that where the driveline meets the rear diff, it's a little loose. Like I can shake it with my hand and it'll rattle. I don't know if that's normal or what, but from my understanding it should be pretty tight with little to no movement. Could be wrong though.

Anyway, I already disconnected the pinion flange so now the driveline is detached from the rear diff (although I suspended it in the air with the jackstand cause I was told to do so). Now my next big question is, how do I get the differential itself off? I am assuming it's going to be one hell of a big pain in the rear because of how old the car is and that it looks like it's almost welded on there (but it's not).

I loosened almost all of the bolts that hold the differential to the housing but, after all of them come off should I just be able to pull the housing straight out or will there be more grunt work involved?

That's about all I have at the moment, if anyone has any ideas or advice please help me. I plan on replacing the differential housing gasket as well, but please understand that this is my first time replacing the pinion seal and I am a regular backyard mechanic so I just want to make sure I am doing this whole gig right.

Thanks again,

Toyomo

BigBluePile

iTrader: (3)

Wow. I would say you need to read an FSM first...I'm just sayin

Toyomo

I have the FSM. Been reading it through and through, and to be honest it's pretty vague on a lot of major repairs aside from this one, but I just want to make sure I am doing this the right way. The job doesn't look difficult and I am just trying to save a little bit of money by doing it my own way.

EDIT: Also, what is this breather tube thingie that I keep hearing about? I heard that if that gets clogged it can cause some issues.

scuba

In order to pull the rear differential, one must pull the axle shafts.

Please tell me how this is vague ?
http://myweb.dal.ca/is353832/93fsm/s...33rearaxle.pdf
http://myweb.dal.ca/is353832/93fsm/s...35differen.pdf

peow130

Scuba is right.
However i will say this.
My truck had the same issues, and it was the pinion bearing in my case.

Toyomo

I have to pull off the entire axle shafts just to get to the differential? Please tell me you're kidding. I thought you could just disconnect the driveline and then unbolt the housing bolts and it should come straight off, why do I need to pull the ale shafts off?

scuba

Not kidding at all. The axle shafts are splined into the differential, with them still in there, no way the diff can come out.

4Crawler

iTrader: (3)

Pinion seal replacement:
- http://www.4crawler.com/4x4/CheapTri...eal/index.html

And there should be NO play in the pinion flange, might just be loose (tighten and see if it runs OK) or you may have damage pinion gear bearings if it has been run loose for a long time.

83

It's REALLY not a big deal to pull the axle shafts. Honestly. If this is super daunting to you, take it to a mechanic, you aren't cut out for working on your own truck
I always second guess my abilities working on my truck, but I replaced my rear diff in an afternoon, alone, with the FSM and looking (search) at some online instructions with photos. I even had to drill 4 new holes in the flange since I put in a later model diff, and that wasn't easy...

It's honestly like this....take off rear driveshaft. Lift rear of truck securely on jackstands. Take off rear tires. Unscrew brake fluid lines from the back of the drums and seal them off so they don't leak all over. Unbolt the (what...4 maybe?) bolts that you uncovered by taking off the tires. Slide the axles out. Take off all nuts from diffe.Take a soft hammer or a hard hammer & bloc of wood and give the diff a couple wacks to loosen it. Pull it out. Someone please correct me if I'm way off on something.

One of those jobs that's really very simple, but makes you feel very manly and like a real mechanic because you're there with the axles out and this big gear box thingy on the garage floor..

peow130

Lol yeah. It's 4 bolts that hold in the axle shafts/drums..
Make sure you drain the axle, though.

Toyomo

I got the differential off, now the problem is I can't get the pinion nut off because the differential gears are moving.

Is there anyway I can get this off, without taking apart the differential gears? Please help me out I am literally two steps away from finishing this job after this bolt gets out.

BigBluePile

iTrader: (3)

impact gun

4Crawler

iTrader: (3)

Best to have broken the pinion nut free before pulling out the axles, use the e-brake and have the weight on the tires and it'll come loose easy. But you can try to find some flat steel stock at the hardware store, then drill 2 holes an one end along the edge to match 2 of the flange holes. Then bolt the bar to the flange and use that to hold it still. I used a piece of 1/8"x2" flat bar about 3' long as I recall. Drill the holes about 13/32" dia. to fit the 10mm bolts.

peow130

I stuck the wooden end of a rubber mallet in my spider gear case deal.. that prevented it from moving.
Then i used the inertia of the whole carrier and broke the pinion loose with my hand.

Toyomo

So you guys are telling me that I didn't have to pull my axle shafts in order to get the pinion nut loosened?


Is this what I am hearing, please someone tell me I am hallucinating and tell me that I didn't waste all that time for nothing....

4Crawler

iTrader: (3)

No. Did you not read the web page I posted earlier? If so, do so now. You can see I did mine with the diff. still in the axle:

BigBluePile

iTrader: (3)

Christ all you wanted to do was tighten up the pinion nut...?

Well, now you know exactly how you rear driveline works! Heck, that's half the battle!

83

Dude, you never said all you wanted to pull was the pinion bearing. Right off the bat you asked how to get the differential out. We told you.

waskillywabbit

iTrader: (-1)

Replacing a pinion seal takes maybe 5 minutes once you remove the dshaft and take the pinion nut off. It is clearly detailed in the Factory Service Manual for your vehicle. Plenty of links here detailing how and plenty of threads pointing newbs to FSMs.

In the future OP, research your project thoroughly, READ and understand the links and advice you are given, then ask intelligent questions, THEN start doing the work. Ready. Fire. Aim only causes grief. You will save yourself a lot of undue labor, parts, money and frustration by doing your homework FIRST, not during.