1988 4Runner · 98 5VZ-FE swap
Truck side
The work on the truck itself: what to pull from the old engine, fuel, body lift, harness and exhaust.
Tick boxes on this page are saved in this browser only. HAVE parts start ticked.
Shop practice unless a step names an FSM page. The engine-side install steps with FSM links are in section 15.
T1. Pull from the 3VZ before you sell it
Status PULL = take it off the 3VZ and bag/tag it. Nothing here starts checked: check each box once it's off and in your pile. Sources: ORS conversion guide ("parts required from a 3.0L 3VZ-E", "Engine Preparation", "Engine Install", "Fuel Hoses", "A/C System", "Under-Hood Completion") plus this project's wiring and engine decisions. When in doubt, keep it: a bolt or bracket costs nothing to keep and a lot to chase later.
Oil, gauges and sensors
| Part on the 3VZ | Used for | When needed | Status |
|---|
| 88 oil pan + its bolts/nuts | The 5VZ's pan (decision). Check the 5VZ strainer clears the pan floor | Oct 20 | PULL |
| 88 dipstick + tube (keep even with the new dipstick kit) | Backup / reference for the dipstick length | Oct 20 | PULL |
| 88 oil pressure sender (gauge type) | Replaces the 98 switch so the 88 oil gauge works. Loctite 243 on 2–3 threads, 15 N·m. Never connect the 88 gauge to the 98 switch (ORS: it can damage the gauge) | Nov 3 | PULL |
| Temp gauge sender (single wire) | The 98 sender reads ~13–16 °F cool on the 88 gauge. Check the thread fits the 5VZ | Nov 3 | PULL |
| Pigtails cut from the 3VZ harness, ~6" with connectors: oil sender and temp sender plugs/terminals (only if the 98 plugs won't fit the 88 senders), A/C clutch, alternator plug (if it's on the engine harness) | The 98 plugs may not fit the 88 sender/compressor | Oct 16 (bench) | PULL |
| Old 3VZ engine harness (at least the N3/N5 mating plugs with ~12" of wire) | Becomes the plug-in conversion pigtail | Oct 16 (bench) | PULL |
| 3VZ harness ground branch (brown wires to the engine ground eyelet): don't cut until wiring check 4 has run. On the bench, beep N5-3 and N5-11 (BR) engine-side cavities to the eyelet; on the truck, Ω from N5-3/N5-11 body side to chassis | The 98 harness has its own ECM grounds (EC eyelets). Only matters if an 88 body circuit grounds through this branch: if so, pin a ground wire into that N5 cavity in the adapter, with a ring terminal to chassis | Oct 16 (bench) | CHECK |
| 88 R150 reverse switch branch and transfer 4WD switch branch, unwrapped whole out of the old 3VZ harness: switch plugs untouched, wires full length back to the N3 plug | Kept as-is; only the N3 end gets re-pinned into the adapter | Oct 16 (bench) | PULL |
A/C (keeping the 88 system)
| Part on the 3VZ | Used for | When needed | Status |
|---|
| 88 A/C compressor: still on the truck, lines attached, system sealed (unbolted from the 3VZ) | Keep it supported so the hoses aren't strained or kinked. When the 5VZ is in: swap on the 5VZ pulley + clutch plate (no refrigerant opened), bolt it to the 5VZ bracket. Keep its mounting bolts | Nov 5 | HAVE-on truck |
| The shim under the 88 compressor's clutch plate | Reuse it when you swap on the 5VZ pulley + clutch plate; without it the clutch stays engaged | Nov 5 | HAVE-on compressor |
| 88 A/C hoses (suction + discharge): still connected; leave them on | Nothing to reconnect. Check the low-side line clears the upper control arm once the compressor is bolted on | Nov 8 | HAVE-on truck |
| 3VZ A/C bracket (keep for reference) | ORS grinds a boss on the 5VZ bracket; compare before grinding | Nov 5 | PULL |
Mounts, bell-housing, starter
| Part on the 3VZ | Used for | When needed | Status |
|---|
| Engine mount brackets (block side) + insulators from the 88 | Not used: checked 2026-10-13, the 88 brackets have a 4-hole rectangle pattern and the 5VZ block has 3 holes (1 top, 2 bottom). Replaced by 91–95 parts (T6) | | N/A |
| Engine mount-to-frame bolts and nuts | Reused on install, 38 N·m | Nov 7 | PULL |
| Every bell-housing-to-block bolt and nut | ORS: reuse the bolts from the transmission's application | Nov 7 | PULL |
| Stiffening brackets (block to lower bell-housing) + bolts | Optional, for strength. 5VZ holes are 10 × 1.25; chase the threads | Nov 7 | PULL |
| Rear end plate (engine plate between block and bell-housing) + bell-housing dust cover | Your 98 engine came from an A/T truck, so its plate may be the A/T type. Compare them; use whichever fits the R150 and clears the flywheel | Nov 4 | PULL |
| Starter bolts (the 3VZ starter itself isn't needed) | 2 bolts, 39 N·m | Nov 7 | PULL |
| Clutch hose bracket (on the RH head) | Moves to the 5VZ RH head, upper rear corner, 2nd hole from the rear | Nov 7 | PULL |
Fuel, vacuum, throttle
| Part on the 3VZ | Used for | When needed | Status |
|---|
| Fuel supply hose + union/banjo bolts + gaskets (hard line → rail) | Fittings for the line at the RH frame rail; ORS adapts from there | Nov 9 | PULL |
| Fuel return hose + clamps | Return line connection | Nov 9 | PULL |
| Throttle cable bracket (on the 3VZ intake) | ORS: the 3VZ cable works with a modified bracket | Nov 8 | PULL |
| Brake booster hose + one-way valve | Reused in the new booster hose; air flows booster → engine | Nov 8 | PULL |
| Vacuum hoses, PCV hose, hose clamps | Spares and fittings | Nov 8 | PULL |
| EVAP canister (if it's on the engine side) | Optional: ORS says the 3VZ canister works | Nov 8 | PULL |
| Air box / intake tube | Only if the Magnuson intake can use them | Nov 5 | PULL |
Cooling, PS, electrical
| Part on the 3VZ | Used for | When needed | Status |
|---|
| Thermostat housing + lower radiator hose | One of the two lower-hose options (shield it from the alternator bracket) | Nov 8 | PULL |
| Upper radiator hose, heater hoses + fittings, clamps | Spares / fittings while you fit new hoses | Nov 8 | PULL |
| PS high-pressure hose + original banjo bolt (and the return hose) | Reused on the 5VZ pump with a new gasket. Keep the return hard line and brackets too | Nov 8 | PULL |
| Engine ground straps (engine → body, engine → battery) | Reuse if in good shape | Nov 8 | PULL |
Already in the truck (not on the engine): just check they're good
| Part | Used for | When needed | Status |
|---|
| Radiator (+ cap) | ORS: use a 3VZ radiator. New or recored if it's tired | Nov 8 | CHECK |
| Overflow tank | Original location | Nov 8 | CHECK |
| Fan shroud | Trim the LH side to clear the 5VZ fan (ORS); the lower cover may not fit | Nov 8 | CHECK |
| Throttle cable | Option: 3VZ cable with the modified bracket (or the 5VZ cable) | Nov 8 | CHECK |
| Battery cables, fusible link | Reuse if they're in good shape | Nov 8 | CHECK |
OK to sell with the 3VZ
| Part | Why | | Status |
|---|
| 3VZ starter, alternator, PS pump, fan, fan clutch | Using the 5VZ ones | | N/A |
| Flywheel, clutch, intake, distributor, igniter/coil, ECU, exhaust manifolds/downpipe/cat | New kit / 5VZ / custom exhaust (3VZ downpipe and cat are too small) | | N/A |
| Bay prep | Notes |
|---|
| Clean and degrease the bay. Inspect the frame mounts, clutch line and slave cylinder. Check the R150 front seal | |
| Check the R150 front bearing retainer seal (replace if leaking) and the transmission mount | |
T2. Body lift (1") and hood
| Step | Notes |
|---|
| 1" body lift | Done (installed) |
| Check the radiator support, shifter boot, steering shaft, fan clearance after the lift | |
| Cut the hood after the engine and Magnuson are in (Nov 18–20). Measure the Magnuson's highest point with the hood shut on clay | Seal the cut edge so it doesn't rust |
| Item | Qty | Spec | Status |
|---|
| 1" body lift kit | 1 | installed | HAVE-you |
| Hood scoop or vent (if you're covering the cut) | 1 | | OPTIONAL |
T3. Fuel: DW200 pump and lines
| Step | Notes |
|---|
| Drop the tank, fit the DW200 with its install kit, new strainer and tank seal | |
| Relay B: battery → 15 A fuse → relay → pump, 14 AWG. Coil from the 88 COR pump output | Wiring sheet 3 |
| Supply and return lines to the 5VZ rail. New 88 fuel filter | |
| Item | Qty | Spec | Status |
|---|
| DW200 255 L/h (replaces the DW100 9-101-1000 you have, 2026-10-18) | 1 | ~9–10.5 A at 40–60 psi: 12 AWG, 20A fuse | BUY |
| DW200 install kit, strainer, tank seal | 1 | | BUY |
| Fuel supply union at the RH frame rail (if the line ends in a male fitting) | 1 | 90404-14014 | CHECK / BUY |
| High-pressure fuel hose to the rail (ORS EC033–EC035A or a custom line) | 1 | | BUY |
| Fuel return hose, 1/4" fuel-injection rated + clamps | ~6 ft | | BUY |
| 88 fuel filter | 1 | | BUY |
| Fuel pressure gauge | 1 | 265–304 kPa (38–44 psi) base | BUY / borrow |
T4. Harness build (bench, any evening)
| Step | Notes |
|---|
| Remove the A/T and transfer branches | Strip list part 1 (in the wiring section below). Watch the 3 shared splices |
| De-pin the ECM pins, E12 pins and II1/II3 cavities you're not keeping | Strip list parts 2–4 |
| Direct plug-in: pin the kept 98 wires (new 88-type terminals) into the N3/N5 halves cut from the old 3VZ harness. Do the reach test first | Build list (wiring section), checks 0a–0c |
| Make the new wires: 6 E12 wires, junctions A–E, 4WD W-B ground (~7 ft → N5-11), Relay B + AC1 relay, DLC3 V → add-a-fuse, ground straps | Build list tables 2–5 |
| Build the relay/fuse panel (Relay A, Relay B, 3 fuses) | |
| Meter N5-12 with the 88 EFI main relay pulled (coil feed or output?) | Wiring sheet 5 |
| Continuity check the whole harness before it goes in | |
| Item | Qty | Spec | Status |
|---|
| Relays (Relay A W-L bus, Relay B pump) + weatherproof sockets | 2 | 30/87/86/85 | BUY |
| Hidden fuel-pump kill switch: small toggle (≥ 1 A) + 18 AWG run to the cab, spade/pinned terminals | 1 | in Relay B coil ground | BUY |
| Fuses 15 A, 15 A, 7.5 A + weatherproof holders | 3 | | BUY |
| 12 AWG wire (DW200 feed + ground to the tank) | ~25 ft | pure copper, GXL/TXL | BUY |
| 14 AWG wire | ~25 ft | | BUY |
| 16 AWG wire | ~25 ft | | BUY |
| DLC3: not needed. The user's pigtail has 12" leads and mounts by the glove box | | | HAVE |
| 88-type terminals for N3/N5 (98 terminals don't fit, tested 2026-10-18): 13 small (+1 if N5-16) and 2 large needed. Measure the de-pinned 88 terminal's blade width to order | 25 small + 5 large | | BUY |
| 98 E12 terminals for the 6 new E12 wires | 10 | | BUY |
| IWISS IWS-1424A open-barrel crimper (24–14 AWG) | 1 | not 1424B / 1420D (Weather Pack) | BUY |
| 18 AWG TXL/GXL pure copper (no CCA, no silicone RC wire) | ~25 ft | | BUY |
| Add-a-fuse matching the 88 fuse type + 7.5A fuse + spade/bullet pair (OBD pin 16) | 1 | constant slot | BUY |
| (Back-up and 4WD switches: their 88 branches are salvaged whole, no pigtails needed) | | | N/A |
| Heavy-duty junction for block A: one heavy 12–14 AWG pinned terminal (no splice); carries starter-solenoid current | 1 | | BUY |
| Joint connectors (bus-bar plug type, pins only) for junctions B–E | 4 | Toyota-style or equivalent | BUY |
| Small 4-pin relay + socket for the ECM A/C idle-up (AC1, E12-16) | 1 | | BUY |
| 39 Ω 5 W resistor (only if the A/C clutch won't engage in check 12) | 1 | | CHECK |
| Ground straps: block → battery −, block → body | 2+ | | BUY |
| Alternator plug pigtail (only if there's no 98 Engine No.2 wire) | 1 | | CHECK |
| A/C clutch adapter pigtail (decided 2026-10-21): plug that mates the 98 A2 clutch plug → short 18 AWG wire → ring terminal on the 88 compressor clutch lead. The 98 harness stays uncut; the 3VZ B-W clutch pigtail isn't needed. Source the A2 mating half (e.g. off a 98 compressor) | 1 | | BUY |
| Terminals, solder sleeves, heat-shrink, split loom, harness tape, P-clamps, zip ties | lot | | BUY |
| Heat-reflective sleeve near the exhaust | lot | | BUY |
| Firewall grommet | 1 | | CHECK |
| De-pin tools, crimper, multimeter | | | have / BUY |
T5. Exhaust: stock 5VZ manifolds + your own crossover
Crossover method: the YotaTech thread "Build your own 3.4 crossover pipe" (89 4Runner). Cut the 98 crossover apart, reshape it and re-weld. The manifolds and their gaskets follow section 6 (FSM EM-56/57).
| Step | Notes |
|---|
| Manifolds on with new gaskets (section 6) before the engine goes in | 40 N·m; heat insulators 8 N·m |
| Remove the crossover heat shield. Cut the factory welds, not the pipes; leave the old weld as a depth mark | Thread: cut-off wheel and die grinder |
| Mark the flex section L/R so it goes back the same way | |
| With the engine in the truck, test-fit and cut the pipe to shape. Add a short spacer pipe if the flex hits the bell-housing bolts | Thread: the flex hit the trans bolts until he added a spacer |
| Check clearance at the trans, head, frame, steering shaft and starter. Tack, re-check, weld fully | Some flanges need an ear trimmed |
| B1S1 O2 sensor: before the cat. If it hits the frame, move the bung | Thread: his O2 hit the frame |
| Downpipe, flex, cat with the B1S2 bung after the cat, muffler, hangers | 2.5" (2.25" min). Don't reuse the 3VZ downpipe or cat |
| Heat shield the firewall, harness, speedo cable and parking-brake cable | |
| Item | Qty | Spec | Status |
|---|
| 98 exhaust manifolds + heat insulators | 2 | warpage max 1.00 mm | REUSE / CHECK |
| 98 crossover pipe (to modify) | 1 | | REUSE / CHECK |
| ◆ Exhaust manifold gaskets | 2 | 40 N·m nuts | HAVE-kit gasket set (seen in kit photo) |
| ◆ Crossover gaskets | 2 | 45 N·m | HAVE-kit gasket set (seen in kit photo) |
| ◆ Crossover-to-downpipe gasket + nuts (FSM marks the nuts one-time-use), if you keep the factory flange | 1 set | 62 N·m | BUY |
| ◆ LH exhaust manifold plug gasket | 1 | | BUY |
| Manifold and crossover studs/nuts (rusty ones break) | set | | CHECK / BUY |
| Short pipe for the spacer, 2.5" tubing and bends | lot | | BUY |
| O2 bungs or flanges: the 98 O2 sensors are 2-bolt flange sensors (FSM EM-101: ◆ gasket, ◆ nuts, 20 N·m), not 18 mm threaded. Weld 98-style flanges, or use threaded bungs with threaded sensors that have the 98 connector | 2 | | CHECK / BUY |
| ◆ O2 sensor gaskets + nuts (flange type) | 2 sets | 20 N·m | BUY |
| Flex coupler (if the 98 flex is bad) | 1 | | CHECK / BUY |
| Catalytic converter (one cat) | 1 | 2.5" | BUY |
| Muffler, flanges + gaskets, hangers | lot | | BUY |
| Heat shielding | lot | | BUY |
| Welder wire, cut-off wheels, die grinder bits | | | BUY |