1st Gen 4Runner Solid Axle Swap and 1UZ Engine Swap
 

Things are about to get funky up in this shop. Got a buddy who has tasked me with helping him swap in a Lexus 1UZ V8 engine into his 1st gen 4Runner (1988) and ditch the IFS for a Toyota solid axle. Oh boy, this is a first for me, and judging on the searches we did, the first either of us has seen. We've seen 1UZ swaps in stock 1st gens, 2nd gens, and 3rd gens (2UZs came stock in 4th Gens). And of course, doing a SAS is nothing new when keeping a stock engine (22R, 22RE, 1-3VZ, etc). But we haven't found anyone who has done both at the same time. We've looked to find answers to issues we are running into. So, I guess we're making it up as we go along.

So here goes...

• The ride is a 1988 Toyota 4Runner IFS all stock with 33" Boggers.
• The Engine is a Toyota 1UZ-FE donated by a 1992 Lexus LS400.
• The Axle is a first-gen narrow Toyota solid axle from a 1984 4Runner.
• The shocks are Radflo 2.0 Coilovers
• The rest... we are making it up as we go!

The Vehicle:

The Engine.

The first night the 4Runner was unloaded and driven into the shop. The front fenders, hood, grille, and bumper were removed. Up in the air to remove the drive shafts and loosen the trans/transfer case cross member (taking it all out as one assembly for ease).

Then the front radiator support was cut temporarily to make getting the old drivetrain assembly out and the bigger engine/drivetrain in and out easy for mock-up (This thing will go in and out of the 4Runner many many times before she's finally sat at home). The radiator, all electronic connections, throttle cables, exhaust, etc. were all removed and finally, the old 22RE and transmission/transfer case came out without a fuss. All in about 4-5 hours.

Day 2
 

The next day the 4Runner gets pushed out of the shop a bit to degrease and pressure wash the engine bay and IFS components to make it a little easier to get them all out.
Attachment 393863

IFS elimination/SAS isn't difficult. Swapping an engine isn't difficult. But doing both at the same time is a bit of a challenge. The engine MUST go in and get permanently mounted BEFORE the SAS is performed. The reason is that I need to know where the engine will sit so I can calculate where to position the solid axle and suspension components so they will not bind or hit the oil pan. And also to keep it at the desired ride height with all the proper geometry and clearances, the engine had to come up a little, axle forward a bit, shock towers modified a bit, then engine over to passenger side a bit to clear steering linkage, etc. and so forth.

Also, here's another rub with this combo of customization, at least in my shop. Yes, I have a lift, but I'm limited on space near the lift in my tiny basement shop. Put the 4Runner on the lift for SAS and leave it there, no problem (like I did with the 3rd gen SAS/insane build). But I can't install an engine in this shop with a vehicle on the lift because there is no room to maneuver the cherry picker due to the wall, workbench, and some other objects in front of the lift.

Solution: My buddy came up with an ingenious solution that I fabbed up quickly. A simple jig made from an old crappy engine stand and some scrap tubing to mount on the front frame cross member. This will allow the engine to be put in with all the IFS suspension cut off, give plenty of room to measure and maneuver, and allow the vehicle to still be pushed forward to go on the lift for final assembly/testing later.
Attachment 393864

Now the IFS can come off!

Attachment 393865

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Now with a clean frame we can check the coil over shock tower placement...

Attachment 393867

Then put the engine in for fitment! A nudge here, wiggle there, snip and cut there and voilà, ready for engine mount fabbing.

Attachment 393868

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Now we are off to the races, the frame is free of the IFS suspension. The Axle is cleaned and ready for building. The engine is positioned perfectly and ready for motor mounts to be fabbed up. Next we strengthen the frame.

Hey everyone, I'm the buddy. I thought I had an account but it's been so long I couldn't find anything.


I've had a list of first gens and love them. This build has been in the works for awhile, but finding someone confident enough to do it, has been the struggle.

The engine is actually a 92 sc400. Has the factory rear sump oil pan, and the big rods.
I will be going sheet metal intake and full standalone, with auto transmission still.

The sas isn't just an sas. It's actually a 4wheel underground 3 link. ( I think the title should be changed. Sas are easy. 3 link not so much ) plus these are badass kits and really the best and easiest thing out there.

My goal and game plan is a 4-6" lift range, with all the flex. I don't want a monster truck, shooting for a badass daily, mountain trip capable, or beach trip capable. I will likely one day turbo it as well. ( I'm crazy I know)

So here we go guys.

LS, SC, I knew it was one of those xx400's. in 1992 everyone liked big rods! :thumb3:

a SAS is a SAS as far as I'm concerned. 3 links, 4 links, Leafs, Magic beans, whatever. Easy to me. :lol:

Well, you should have come to me first. :lol:
Either way, going to be a fun build. Let's engineer it! :cheers:

nice! following, look forward to see how you get everything to fit. details on exhaust routing, steering shaft, and how axle placement and coil towers all fit together are getting me excited!

Your gonna love the 4wu link ride.

its ALL been done😂😂 a few times at least. Ive got a number of build threads somewhere, not too inspired to hunt them down atm.

an 89. long progression. but linked with a 1uz
My Anorexic Toy | Pirate 4x4

funny, i actually have the 1uz and pile o parts to swap in the garage, 4wu linked my 87 runner, and was hot do do the swap ..... all back in 2013. Life
Now ive got another 87 T4R and gonna put it in there, linked of course😎. eventually😂😂

hope you'll inspire me🍺.

By the looks of exhaust ( laying under there with the link held up where I think it will land ) it will be tight, but won't be too bad.

Steering shaft, I'll have to upload pictures, but I think we will be okay with a normal straight one, just longer. We have motor slightly passenger side.

We are pushing axle forward a little, and I am not going to used this to it's full potential. I won't be going crazy flex, I won't be doing any hardcore shit.

This will be a low ride height, mostly daily. I have seen a couple linked 1uz, but all on big tires and off road rigs. So being tucked up in there is a big difference in mine, vs most others.

Hurry up and get back to it. I am going fancy standalone and intake. One day I'll get bored and turbo it.

I'll check out your thread here shortly.

post lots of progress!!
all good shi* 🤙

https://hosting.photobucket.com/albu...720&fit=bounds

Sub'd.

Very well.

Have any flat ground pics? What size tires?

Also not sure where you guys measure frame height to get these numbers. The stock ifs was sitting around 24" at the front crossbar


I need to upload pictures, and Brent needs to post updates lol

SAS is an interchangeable term like SAC which a 4WUG link kit is considered.
what coil springs/bump stops/limit straps are you going with?
How about your steering system? full hydro may not be the best for a DD

Looking forward to this build, I plan on a 1uz myself this fall..

Annnnd Quick update... I've been balls to the wall with a new job and kids the last few months. :shrug:

BUT!!! August is coming up and when I get back from working south FL the last week of July (I know so horrible working with clients on the beach for a week) I plan on getting back in the shop and getting some shit done.

Life happens... :yield:

SAS is as SAS does. And life is like a box of random parts, you never know what you're going to get... unless they are clearly marked similar to a box of chocolates. :yo: