Hear ye hear ye, I have returned from the mountaintop, and I have seen the light ye lowly peasants, for I am now become the master of the mechanical arts!
Actually, this kinda sucked, so muhc time I'll never get back. But hey I did it, so here we go.
Well some of you may know I've toyed around with the idea of converting my 2wd r50 "Jennifer" to 4wd. I had collected a few parts for a while but the project was put on severe hold when I bought my 90 4runner and subsequently blew up its engine and dropped in a new one. Now unlike SOME people on here I didn't get rid of my beloved R50 when buying a 4wd 4runner (Just kidding MJO, I know it hurts man), but I pondered the wisdom of converting my truck when i now had a perfectly good (clapped out) 4wd trail rig. Well ultimately it was a matter of convenience, My rear main seal had been puking for a while and a while back I had it replaced by some guys I worked with, well it kept leaking afterward, they said it was the pan, so i paid them to do that too, and then a week later it was leaking worse. I wasn't contacting them anymore so i just dealt with it for a while. Well once I got the yota running again the leak continued to worsen and having been screwed literally every time I took my car to someone (a supposedly reputable shop replaced my f*cking RESONATOR when I paid for a CAT replacement, and they welded it in so it's almost impossible to remove the exhaust), I decided to handle this myself. Now, parts. If you're looking into this swap there's some question about parts, I acquired mine over a long time, over a year.
So there are two other major threads of people doing this:
and the best one i've seen:
So what parts work with what?
Transfer cases are all the same, get a tx10 manual case and you're golden
Front hubs/brakes are only different between the pre/post facelift r50s, more specifically by what engine they have.
The front r200a differential and mounting brackets are all the same. my 2wd r50 even has bolts in the subframe to go through to bushings.
Now the rear driveshaft/diff, there's some misinformation. All 2001 and prior r50s, including 2001s with VQs, have a 4 bolt drive flange on the differential that matches up with the 4wd driveshaft. In 2002 Nissan used a 4 bolt output from the trans that goes to a 6 bolt Cardan joint. You'll need a drive flange or hole 3rd member from a 4wd if you're 2002 or later. You might, like me, thing you can pull the flange off your 2wd trans because it has the same bolt pattern and spline count, but the splines themselves are different shapes, so you're gonna need a 4wd rear end or flange, good time to grab an LSD unit.
Transmissions: This was the big point of contention, what year trans works with what. To be sure you'll want to go to nissan's OEM parts site and cross reference adjoining years to what you've got. My truck is a 11/01, and i know it's year range starts on 07/01, I used an 05/02. Call around, find out what you can, compare wiring connectors. I will say that while all my connectors were the same, I did have an extra orange wire on my 4wd trans, and I couldn't find a single wiring diagram in the FSM, on alldata, or identifix that showed what it was. I rolled the dice and slapped the thing in anyway.
So back to my story. I frequent 2 local junkyards here in Jacksonville FL, and pulling heavy stuff in the heat is a pain, but on one trip around veterans day I think 2 years ago, I found an R50 missing it's transmission, but the tx10, driveshaft, and crossmember were laying loose under it. I pinched that stuff right quick, and it was a 50% off day! Paid elss than 75$ for the whole deal. Later on I swiped a set of hubs and front diff for around 125$, and then a few months back my big score: I was searching for toyota parts but i noticed a maroon R50 that had the same wheels and roof rack as mine, probably the same year. I looked inside, door date was 05/02, and I could see the interior panel where the tx10 shifter came through. I popped the hood and the engine was gone and the transmission was sitting vertically in the bay with the transfer case attached! I ran up front and grabbed an engine hoist and let me tell you, maneuvering that thing on my own on gravel is the of the hardest things I have ever done, but I managed to shove that thing into the back of the 4runner and haul back home, and it was another half off day! 75$ for a trans! I dragged it to the shop and took off the pan, super mint inside, so I resealed it and called it a day. And then I got down to it.
Now, replacing a transmission, or even whole drivetrain, is something a competent mechanic can do, even in a garage. However, I DO NOT recommend you or ANYONE replace the oil pan gasket without a car lift. My shop couldn't spare a bay for several days so I was stuck in my uncles garage. To remove the oil pan on a VQ R50 the subframe MUST come down and the engine MUST lift up. This is NOT a fun thing to do. And it's even less fun lining it all back up, it took two other people and my hand got crunched by the passenger motor mount. Seriously, do not ever do this. Sometimes you've gotta bite the bullet and pay up.
But to counter that, once i got the trans out I figured out why my leak had gotten worse: The dudes who put my rear main seal in botched it and the rubber tore, so the metal spring inside the seal had been rubbing my crankshaft for months. And the whole deal had about a half pound of RTV on it. That was from when they supposedly did the oil pan gasket, but looking at the pan and seals when it was all off, I seriously doubt they dropped that pan. I think they saw how messed up the seal was and dumped RTV on it and called it a day. I'm over it now, and I'm past holding grudges, but that just freaking bothers me. Luckily I had the forethought to order a repair sleeve before digging into this because that jacked up seal had worn a gnarly groove into the rear of my crankshaft. That went on no problem but it was too long, it stuck out past the end of the crank so the flexplate wouldn't bolt on, so I got to grind down the sleeve hunched over under a car on jackstands, and it was about that time I started regretting that part of this deal. But I got it all back together and also installed a catalytic converter to replace the one the first shop SAID they had. Next piece of advice: buy a good hydraulic trans jack. I cheaped out and bought a scissor type trans jack that was a massive pain. Also take a long, and I mean LONG look at your bell housing and rear engine bolt patterns. I spent, no lie, about 3 hours fighting with this damn trans trying to get it to line up before realizing my trans and engine had dowel pins in the exact same place, pointing at each other. Why? Hell if I know. I cut em both off and ground them flat, luckily I had another dowel on the trans that lined up perfect. After that I fit up the crossmember, which only took a little bit of cursing and shouting. Now, the factory 2wd exhaust can fit the transfer case, but my uncle and I had to lift leaned forward and hook the output housing over the exhaust pipes and then line it up. After that it's just Driveshaft stuff. Also, for the 4wd shifter, there's a black sheet metal plate under the trans shifter that unbolts, the 4wd one has a slot for the tx10 shifter, but you can just cut a hole in your existing one.
So my current status. I Put fluid in the trans, but I did so with the transfer case out so a bunch of it leaked out the output housing, I just wanted to see the trans move before I finsihed the rest of the work. So the end result was that I finished the job not knowing how much trans fluid was in the thing. She started up fine and drove but it was slipping a lot, so i gradually added more. Eventually I felt comfortable enough to drive the thing up to the shop and It made it, but it still slipped some and it didn't seem to want to decide between 3rd and 4th at around 50 MPH, but i think I just gotta add some more fluid and tighten up the crankshaft position sensor wiring. So, that's all I've got for now, I still gotta make it reliable and put in the front end parts, but I drove a 4wd drivetrain converted pathfinder about 15 miles yesterday. I'll post more (and hopefully pics) sometime tomorrow.