4Runner Gearbox Drama

Now the 'lux had started to get a whiny/grinding noise in the gearbox, it had been there for about 3 months. A definate decellerate "whrr-rrr-rrr" with a bit of a "keck...keeeck...kek" along the way down. Quiet at first, but progressively getting louder as the months went past.

What can you do? The gearbox on a 4x4 is wedged in between the engine and the transfer case, so you don't just pop off a prop shaft and a few nuts for a look, it's an event. So, thinking back to a gearbox I had once before that had the same problem but keep going until I was finally sick of the noise and replaced it - I left it alone.

True to Murphys laws, about 300km from Perth it finally let go. Popped out of gear. "Hmm, that's bad." Try to jam it in gear. Crk, Crrrk, kek. Nope. Pull over, look underneath to see all the oil leaking out. "Well that about wraps that up then."

Fortunately I was on a downhill run into a town, so I rolled in. Much to my amazement and good fortune, Sunday and all, I got on the horn to the RAC and someone even came out! After talking with him, I decided that him being a local mechanic I would just leave the car with him to fix for me. Not that it was *that* easy...

The source of the problem; yes, that used
to be the front cluster gear bearing.

The local mechanic, obviously having been around, said "I'm not going to source a secondhand box for you, because I can't guarantee it. The cost of a new or reconditioned box is probably more than the car is worth." Hmm. "How about I get something in Perth and send it down, and you pull out the old and put in the new?"

Three options I found (2005); a reconditioned unit $AUD1,650; a second hand unit from a wrecker $990, or a second hand out of the paper for $200-800. After talking to a few people I decided that (a) it was probably just the gearbox broken and not the transfer case as well, so I don't need to source a transfer case; (b) The 5 speed box is called a G52 and was used on 'luxes from about 1984 through to 1996 with the only difference being one model that was electronic transfer case shift, the other manual transfer case shift and (c) They tend to last for about 250,000kms before they break.

Looking at bellhousing.

Looking at transfer case end.



I found that there were a few up for grabs from everywhere. Wreckers had some, the best I found was one with 190,000km on the clock. I ruled out the recon one; just too much money to spend on an old car. There were at least 5 in the quokka. One guy had one that he said had been reconditioned by the previous owner and he'd only driven it for about 5,000km before he rolled it. He was asking $500, I took it for $450. Visually I could see it had been split and put back together with new gaskets and blue gasket goo, so it probably had been reconditioned. You can't actually tell anything about a gearbox until it is running. I could select all the gears, so that was that.

Drained the oil, degreased it, boxed it and put it on a freight truck to Bridgetown. The mechanic got it, pulled out the gearbox+transfer case, split them, joined up the new box and put it back on. I also sourced the joining gasket and a new clutch - while it was out may as well give it a birthday.

Eventually I got back down there and got back in the 'lux and drove it home with the old gearbox in the back for investigation. It was driving fine, no whines or whirrrs, so with any luck it will be good for another 250,000kms. As the earlier picture showed, behind the bellhousing the front clustergear bearing had collapsed. You could probably replace that bearing; the gears didn't look like there was any damage. Too hard; the truck is going again, the old gearbox will be picked up in the next bulk rubbish collection...