Editing Z31/Nuts and Bolts

= Z31 Nuts & Bolts — Thread Sizes and Torque Specs =

Reference tables for Z31 (1984–1989 Nissan 300ZX) fasteners. '''Every value on this page carries a source.''' Thread sizes come from G-E's measured list (xenonzcar.com / z31.com) and the Z31Performance forum; torque values come only from the 1987 Factory Service Manual (FSM). A dash (—) means no source on this site gives that value yet.

* '''Torque''' is the FSM range in N·m and ft-lb. The FSM is mainly the 1987 edition. The 1986 edition (OCR) was used to confirm values and to source 1984–86 differences, and rows are labelled with the year(s) whose manual was checked. No 1988–89 manual has been checked yet.
* '''Where a thread size and an FSM torque share a row, they were matched by the part's name.''' The FSM tables don't give thread sizes, so check the pairing on the car before relying on it.
* Values that were on an earlier version of this page but could not be found in any source are listed under [[#Unverified — not yet found in FSM|Unverified — not yet found in FSM]] at the bottom. '''Do not use them without checking.'''

== How to verify ==

Each torque cell cites the FSM section and page (e.g. "FSM EM-45"). The 1987 FSM has a '''Service Data and Specifications (S.D.S.) — Tightening torque''' table near the end of each section:

{| class="wikitable"
! Table on this page !! FSM section !! S.D.S. torque page (1987)
|-
| Engine (block, head, manifolds, turbo) || EM — Engine Mechanical || EM-45 (procedures: EM-23 head/cam sprocket, EM-24 intake manifold, EM-31 main caps, EM-32 rods)
|-
| Engine lubrication & cooling || LC — Engine Lubrication & Cooling || LC-15 (lubrication), LC-16 (cooling)
|-
| Manual transmission || MT — Manual Transmission || MT-8 (installation bolts), MT-57 (FS5W71C), MT-58 (FS5R30A)
|-
| Automatic transmission || AT — Automatic Transmission (E4N71B) || AT-92
|-
| Driveline (propeller shaft, R200 differential) || PD — Propeller Shaft & Differential Carrier || PD-30, PD-31
|-
| Rear axle, drive shafts, rear suspension || RA — Rear Axle & Rear Suspension || RA-24
|-
| Brakes || BR — Brake System || BR-21
|-
| Front axle & front suspension || FA — Front Axle & Front Suspension || FA-25
|-
| Steering || ST — Steering System || ST-23
|-
| Maintenance items (plugs, wheel nuts, seat belts) || MA — Maintenance || MA-41 to MA-43
|}

The FSM PDFs are linked from [[Z31/z31fsm_php|Z31 Factory Service Manuals]]. GI-18 has the standard-bolt torque chart for bolts the section tables don't list. Page numbers are the printed page footers. Where a footer is missing from the text copy (FA-25, RA-24, AT-92), the page is worked out from the footers on either side.

== Engine ==

=== VG30E/ET block, head and manifolds ===

{| class="wikitable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Main bearing cap bolts || — || 1986–87 || 90–100 || 67–74 || FSM EM-45 (1986 & 1987) [3][14], EM-31. Tighten in order, in two or three stages.
|-
| Connecting rod cap nuts || — || 1986–87 || 44–54 || 33–40 || FSM EM-45 (1986 & 1987) [3][14], EM-32. FSM: oil the threads and nut seating surfaces.
|-
| Cylinder head bolts || — || 1987 || see notes || see notes || FSM EM-23 [3]. Procedure: (1) all to 29 N·m (22 ft-lb); (2) all to 59 N·m (43 ft-lb); (3) loosen all completely; (4) all to 29 N·m (22 ft-lb); (5) all to 54–64 N·m (40–47 ft-lb), or turn 60–65° with an angle wrench. Bolt lengths: 127 mm and 106 mm (positions in FSM figure).
|-
| Camshaft sprocket bolts || M10 × 1.25, measured at 28 mm (30 mm also works) || All || 78–88 || 58–65 || Size: rev 7952 contribution (Z31-R chat) [13]. Torque: FSM EM-23, EM-45 [3]; 1986 EM-45 "Camshaft pulley" same [14]; same values as the lemon-manuals.la reference cited in that edit [13].
|-
| Rocker cover bolts || — || 1986–87 || 1–3 || 0.7–2.2 || FSM EM-45 (1986 & 1987) [3][14]
|-
| Rocker shaft bolts || — || 1986–87 || 18–22 || 13–16 || FSM EM-45 (1986 & 1987) [3][14]. Tighten in two or three stages (EM-24).
|-
| Oil pan bolts || M6 × 1.0, 14 mm, bolt + split washer || All || 5–7 || 3.6–5.1 || Size [1]; torque FSM EM-45 [3]; same in 1986 EM-45 [14]
|-
| Oil pan drain plug || — || 1986–87 || 29–39 || 22–29 || FSM EM-45 (1986 & 1987) [14], MA-42 [3][12]
|-
| Spark plugs || — || 1986–87 || 20–29 || 14–22 || FSM EM-45 (1986 & 1987) [14], MA-18, MA-42 [3][12]
|-
| Harmonic balancer (crank pulley) to crank || M10 × 1.0, 120 mm, bolt + flat washer || 84–87 || rowspan="3" | 123–132 || rowspan="3" | 90–98 || Size [1]. Torque: FSM EM-45, MA-22 [3][12]; same in 1986 EM-45 [14].
|-
| Harmonic balancer (crank pulley) to crank || M12 × 1.25, bolt + flat washer || 88–89 || Size [1] (length not recorded).
|-
| Crank pulley bolt (G-E's sample) || M12 × 1.25 × 80 mm, washer 35 mm OD × 8 mm thick || not stated || Forum, G-E 2014-08-12 [2]. G-E asked for someone to check this against other cars.
|-
| Pulleys to harmonic balancer || M6 × 1.0, 15 mm, bolt + split washer || All || — || — || Size [1]
|-
| Flywheel to crank (manual) || M10 × 1.0, 24 mm long (3 mm shoulder), JIS flange head || not stated || 98–108 || 72–80 || Size: forum, G-E 2014-12-28 [2] (his earlier post guessed ~30 mm). Torque: FSM EM-45 (1986 & 1987) [3][14].
|-
| Pressure plate to flywheel || M8 × 1.25, 17 mm long (4 mm shoulder), JIS flange head || not stated || — || — || Forum, G-E 2014-12-28 [2]
|-
| Drive plate to crankshaft (automatic) || — || 1987 || 137–157 || 101–116 || FSM AT-92 [6]
|-
| Timing belt tensioner nut || M10 × 1.25, nut + flat washer || All || 43–58 || 32–43 || Size [1]; torque FSM EM-45, MA-20 [3][12]; same in 1986 EM-45 [14]
|-
| Thermostat housing || M8 × 1.25, 72 mm, bolt + split + flat washer || All || rowspan="2" | 16–21 || rowspan="2" | 12–15 || Size [1]; torque FSM LC-16 "Thermostat housing securing bolt" [4]
|-
| Thermostat housing cover || M8 × 1.25, 34 mm, bolt + split + flat washer || All || Size [1]
|-
| Intake manifold nuts || — || 1987 || 1st: 3–5; 2nd: 24–27 || 1st: 2.2–3.6; 2nd: 17–20 || FSM EM-24 [3]. Tighten in two or three stages.
|-
| Intake manifold bolts || — || 1987 || 1st: 3–5; 2nd: 16–20 || 1st: 2.2–3.6; 2nd: 12–14 || FSM EM-24 [3]
|-
| Exhaust manifold || M8 × 1.25 studs || 84–87 || rowspan="2" | 18–22 || rowspan="2" | 13–16 || Size [1]. Torque: FSM EM-45, 1987 [3] and 1986 [14] (not yet checked for 88–89).
|-
| Exhaust manifold || M10 × 1.25, 30 mm bolts || 88–89 || Size [1]
|-
| Turbocharger unit (ET) || — || 1986–87 || 44–54 || 33–40 || FSM EM-45 (1986 & 1987) [14] "Turbocharger unit" [3]
|-
| Turbine to downpipe (ET) || M10 × 1.5 studs || All || — || — || Size [1]
|-
| Turbo oil feed tube (ET), at cylinder block || — || 1986–87 || 15–20 || 11–14 || FSM EM-45 (1986 & 1987) [14] "Oil feed tube"; LC-15 "Oil inlet tube to cylinder block" [3][4]
|-
| Turbo oil inlet tube (ET), at turbocharger || — || 1987 || 8–11 || 5.8–8.0 || FSM LC-15 [4]
|}

=== Lubrication ===

{| class="wikitable sortable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Oil pump bolts || M6 × 1.0, 20 mm and 30 mm, bolt + split washer || All || 6–7 || 4.3–5.1 || Size [1]; torque FSM LC-15 (M6 securing bolt), EM-45 [4][3]
|-
| Oil pressure switch (sender) port || 1/8" BSPT || All || 13–17 || 9–12 || Size [1]; torque FSM LC-3, LC-15 "Oil pressure switch" [4]
|-
| Oil temperature sensor bung (turbo) || M16 × 1.5 || All (turbo) || — || — || Size [1]. Note: M16 × 1.5 is the oil ''temperature'' bung, not the pressure sender.
|-
| Oil filter bracket to cylinder block || — || 1987 || 14–18 || 10–13 || FSM LC-15 [4]
|-
| Oil filter stud || — || 1987 || 59–74 || 43–54 || FSM LC-15 [4]
|}

== Transmission ==

=== Manual (FS5W71C / FS5R30A / FS5R90A) ===

The 1987 FSM covers the FS5W71C and FS5R30A gearboxes [5]. The 1986 FSM covers the FS5W71C and the BW T-5 (FS5R90A) [14].

{| class="wikitable sortable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Transmission-to-engine bolts No. 1 & 2 || — (length 65 mm / 60 mm) || 1987 || 39–49 || 29–36 || FSM MT-8 [5]. Bolt positions in FSM figure.
|-
| Transmission-to-engine bolts No. 3 & 4 || — (length 55 mm / 25 mm) || 1987 || 29–39 || 22–29 || FSM MT-8 [5]
|-
| Transmission to engine || — || 1986 || 39–49 || 29–36 || FSM 1986 MT-32 (single value in the S.D.S. table) [14]
|-
| Drain and filler plugs (FS5W71C, FS5R30A) || — || 1986–87 || 25–34 || 18–25 || FSM MT-57 (FS5W71C), MT-58 (FS5R30A), MA-24, MA-43 [5][12]; 1986 MT-32 (FS5W71C) [14]
|-
| Drain and filler plugs (BW T-5 / FS5R90A) || — || 1986 || 20–34 || 14–25 || FSM 1986 MT-32 [14]
|-
| Rear mounting insulator to crossmember || — || 1986 || 31–42 || 23–31 || FSM 1986 MT-32 [14]
|-
| Rear mounting insulator to rear extension || — || 1986 || 31–42 || 23–31 || FSM 1986 MT-32 [14]. The 1987 MT table says "Refer to section EM".
|-
| Crossmember to body || — || 1986 || 31–42 || 23–31 || FSM 1986 MT-32 [14]
|-
| Transmission mount to body || M10 × 1.5, 20 mm bolt || All || — || — || Size [1]
|-
| Transmission mount to isolator || M10 × 1.25, 20 mm (90 mm) bolt || All || — || — || Size [1].
|}

=== Automatic (E4N71B) ===

The 1986 and 1987 FSM AT sections both cover the E4N71B [6][14].

{| class="wikitable sortable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Converter housing to engine || — || 1986–87 || 39–49 || 29–36 || FSM AT-92 [6]; 1986 AT-91 [14]
|-
| Drive plate to torque converter || — || 1986–87 || 39–49 || 29–36 || FSM AT-92 [6]; 1986 AT-91 [14]
|-
| Drive plate to crankshaft || — || 1986–87 || 137–157 || 101–116 || FSM AT-92 [6]; 1986 AT-91 [14]
|-
| Oil pan to transmission case || — || 1986–87 || 5–7 || 3.6–5.1 || FSM AT-92 [6]; 1986 AT-91 [14]
|}

== Driveline ==

{| class="wikitable sortable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Propeller shaft to differential companion flange || M10 × 1.25, 30 mm bolt || All (turbo) || 39–44 || 29–33 || Size [1]; torque FSM PD-30, PD-31 [7]
|-
| R200 drive pinion nut || M20 × 1.5 prevailing-torque nut || not stated || 186–294 || 137–217 || Size: forum, G-E 2014-08-12 [2]; torque FSM PD-31 [7]
|-
| Differential cover (rear cover) bolts || M8 × 1.25, 25 mm || All || 16–24 || 12–17 || Size [1]; torque FSM PD-31 "Rear cover fixing bolt" [7]
|-
| Differential mount to body — bolt || M10 × 1.5, 60 mm || All || 29–39 || 22–29 || Size [1]; torque FSM PD-31, RA-24 "Mounting insulator / mounting bracket to body — Bolt" [7][10]
|-
| Differential mount to body — nut || M12 × 1.25 nut || All || 59–78 || 43–58 || Size [1]; torque FSM PD-31, RA-24 "… to body — Nut" [7][10]
|-
| Differential carrier to crossmember (suspension member) || M12 × 1.25, 25 mm (150 mm) bolt || All || 59–78 || 43–58 || Size [1]; torque FSM PD-31, RA-24 [7][10]
|-
| Differential to bracket || M14 × 1.5/2.0 stud, M14 × 1.5 nut || All || — || — || Size [1]. Possibly the FSM's "Rear cover to mounting insulator" (PD-31: 88–118 N·m, 65–87 ft-lb) or "Differential carrier to mounting insulator" (RA-24: 98–118 N·m, 72–87 ft-lb). The two FSM tables differ, so neither is paired here.
|-
| Drive shaft (half-shaft) to companion flange || — || 1987 || Turbo 59–69; non-turbo 39–49 || Turbo 43–51; non-turbo 29–36 || FSM RA-24; PD-31 lists the same values as "Drive shaft to rear axle" [10][7]
|-
| Rear wheel bearing lock nut (axle nut) || — || 1987 || 294–392 || 217–289 || FSM RA-24 [10]
|}

== Brakes ==

{| class="wikitable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Front caliper pin bolts (torque member to cylinder body) || — || 1987 || 22–31 || 16–23 || FSM BR-21 [8]
|-
| Rear caliper pin bolts || — || 1987 || 31–41 || 23–30 || FSM BR-21 (CL14HVB caliper) [8]
|-
| Rear caliper pin bolts || — || 1986 || 22–31 || 16–23 || FSM 1986 BR-20 (CL14H / CL14HB calipers) [14]
|-
| Front caliper bracket (torque member) to strut || M12 × 1.25, 40 mm bolt || All || 72–97 || 53–72 || Size [1] "Caliper to strut"; torque FSM BR-21, FA-25 [8][9]
|-
| Rear caliper bracket (torque member) fixing bolt || — || 1987 || 38–52 || 28–38 || FSM BR-21, RA-24 [8][10]
|-
| Front disc rotor to wheel hub || — || 1986–87 || 59–69 || 43–51 || FSM BR-21, FA-25 [8][9]; 1986 BR-20 [14]. The 1986 FA-24 table reads 49–69 N·m (36–51 ft-lb), which may be an OCR error.
|-
| Brake booster to master cylinder || — || 1987 || 8–11 || 5.8–8.0 || FSM BR-21 [8]
|-
| Brake tube flare nuts || — || 1987 || 15–18 || 11–13 || FSM BR-21 [8]
|-
| Brake hose connector || — || 1987 || 17–20 || 12–14 || FSM BR-21 [8]
|-
| Wheel nuts (acorn, 60° taper) || M12 × 1.25 || 84–86 || 78–98 || 58–72 || Size [1]. Torque: FSM 1986 FA-24, RA-24, MA-42 [14]
|-
| Wheel nuts (lug, 60° taper) || M12 × 1.25 || 87–89 || 98–118 || 72–87 || Size [1]. Torque: FSM 1987 FA-25, RA-24, MA-43 [9][10][12]. Not yet checked against an 88–89 manual.
|}

== Suspension & steering ==

=== Front ===

{| class="wikitable sortable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Knuckle arm to strut (knuckle spindle) || M12 × 1.25, 40 mm bolt || All || 72–97 || 53–72 || Size [1] "Knuckle to strut"; torque FSM FA-25 "Knuckle arm to knuckle spindle" [9]
|-
| Strut mounting insulator (top mount) fixing bolt || — || 1987 || 31–42 || 23–31 || FSM FA-25 [9]
|-
| Transverse link (lower control arm) to suspension member || — || 1987 || 93–113 || 69–83 || FSM FA-25 [9]. FSM: do the final tightening at curb weight with the tires on the ground.
|-
| Lower ball joint to knuckle arm || — || 1987 || 96–120 || 71–88 || FSM FA-25 [9]
|-
| Stabilizer bar to transverse link || — || 1987 || 16–22 || 12–16 || FSM FA-25 [9]
|-
| Stabilizer bar to connecting rod || — || 1987 || 64–69 || 47–51 || FSM FA-25 [9]
|-
| Stabilizer bar clamp to body (tension rod bracket) || — || 1987 || 29–39 || 22–29 || FSM FA-25 [9]. FSM: do the final tightening at curb weight with the tires on the ground.
|-
| Tension rod bracket || M10 × 1.25, 25 mm bolt || All || — || — || Size [1]. FSM FA-25 has "Tension rod bracket to body" 29–39 N·m (22–29 ft-lb); not paired, because it's unclear whether this is the same bolt.
|-
| Tension rod studs (nut) || M10 × 1.5 || 84–87 || — || — || Size [1]
|-
| Tension rod studs (nut) || M12 × 1.5 || 88–89 || — || — || Size [1]
|-
| Tension rod to tension rod bracket || — || 1987 || 44–54 || 33–40 || FSM FA-25 [9]
|-
| Tension rod to transverse link || — || 1987 || 42–54 || 31–40 || FSM FA-25 [9]. The 1986 FA-24 table reads 42–59 N·m (31–43 ft-lb) [14].
|-
| Steering rack (gear & linkage) mounting || M12 × 1.25, 30 mm bolt || All || 39–49 || 29–36 || Size [1] "Steering rack to crossmember"; torque FSM ST-23 [11]
|-
| Tie rod end to knuckle arm || M14 × 1.5 castle nut || All || 54–98 || 40–72 || Size [1]; torque FSM ST-23 "Tie-rod to knuckle arm", FA-25 [11][9]
|-
| Tie rod lock (jam) nut || — || 1987 || 78–98 || 58–72 || FSM ST-23, FA-25, MA-43 [11][9][12]
|}

=== Rear ===

{| class="wikitable sortable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Shock absorber lower end fixing bolt || M12 × 1.25 bolt; M12 × 1.25, 40 mm (80 mm), prevailing-torque nylock nut || All || 59–78 || 43–58 || Size [1] "Shock to lower mount"; torque FSM RA-24 [10]
|-
| Shock absorber upper end || M10 × 1.25 prevailing-torque nuts (upper mount to body) || All || 31–42 || 23–31 || Size [1] "Shock upper mount to body"; torque FSM RA-24 "Upper end fixing bolt" [10]. Pairing by name; check that these are the same fasteners.
|-
| Stabilizer bar to suspension arm || — || 1987 || 16–21 || 12–15 || FSM RA-24 [10]
|-
| Stabilizer bar clamp to suspension member || — || 1987 || 31–42 || 23–31 || FSM RA-24 [10]
|-
| Suspension member to suspension arm (rear arm pivot) || — || 1986–87 || 98–118 || 72–87 || FSM 1986 RA-24 [14]. The 1987 RA-24 table has the same values, but its label is garbled in the text copy [10]. FSM: do the final tightening at curb weight with the tires on the ground (RA-18).
|-
| Suspension member to suspension member stay || — || 1987 || 78–108 || 58–80 || FSM RA-24 [10]
|-
| Suspension member stay to body || — || 1987 || 20–25 || 14–19 || FSM RA-24 [10]
|}

FSM RA (1987, RA-18): tighten the suspension arm pin nuts to the specified torque after the wheels are installed and the car is on the ground at curb weight.

== Body & interior ==

{| class="wikitable sortable"
|-
! Location !! Thread (size × pitch, length) !! Years !! Torque (N·m) !! Torque (ft-lb) !! Source / notes
|-
| Rear seat belt anchor bolt || — || 1987 || 35.8–45.6 || 26.4–33.6 || FSM MA-41 [12]
|-
| Seat bracket || M10 × 1.5, 25 mm bolt || All || — || — || Size [1]
|-
| Front bumper cover || M6 × 1.0 prevailing-torque nuts || All || — || — || Size [1]
|-
| Rear bumper cover || M5 × 1.0 prevailing-torque nuts || All || — || — || Size [1]
|}

For engine accessory, cooling, induction and other fasteners not listed here, see the full measured list at [[Z31/nuts bolts php|Z31 Nut and Bolt List]] [1].

== Sources ==

# '''xenonzcar / z31.com — G-E's measured Z31 nut & bolt list.''' Archived copy: [[Z31/nuts bolts php]]; live: https://www.xenonzcar.com/z31/nuts_bolts.php (same table as the z31.com DokuWiki page ''resources:nuts-and-bolts''; counted as one source).
# '''Z31Performance forum, "Nuts and Bolts" (z31-basics / reference, 2014)''': G-E's posts of 2014-08-07, 2014-08-12 and 2014-12-28. [[Forums/Z31P/z31-basics reference/Nuts and Bolts]].
# '''FSM 1987 §EM''' — Engine Mechanical. S.D.S. Tightening torque EM-45; Cylinder head installation EM-23/EM-24; Main bearing EM-31; Connecting rod EM-32.
# '''FSM 1987 §LC''' — Engine Lubrication & Cooling. Oil pressure check LC-3; S.D.S. LC-15 (lubrication), LC-16 (cooling).
# '''FSM 1987 §MT''' — Manual Transmission. Installation bolt table MT-8; S.D.S. MT-57 (FS5W71C), MT-58 (FS5R30A).
# '''FSM 1987 §AT''' — Automatic Transmission (E4N71B). S.D.S. Tightening torque AT-92.
# '''FSM 1987 §PD''' — Propeller Shaft & Differential Carrier (R200). S.D.S. PD-30, PD-31.
# '''FSM 1987 §BR''' — Brake System. S.D.S. Tightening torque BR-21.
# '''FSM 1987 §FA''' — Front Axle & Front Suspension. S.D.S. Tightening torque FA-25; Transverse link removal & installation.
# '''FSM 1987 §RA''' — Rear Axle & Rear Suspension. S.D.S. Tightening torque RA-24; Suspension arm installation RA-18.
# '''FSM 1987 §ST''' — Steering System. S.D.S. Tightening torque ST-23.
# '''FSM 1987 §MA''' — Maintenance. Spark plugs MA-18; Timing belt MA-20/MA-22; Seat belts MA-41; S.D.S. MA-42/MA-43.
# '''Revision 7952 (2026-05-24, anonymous contributor)''': camshaft sprocket bolt size "as found in Z31-R chat"; torque referenced from [https://lemon-manuals.la/Nissan-Datsun/1984/300ZX%20V6-2960cc%20SOHC%20Turbo%20%28VG30ET%29/Repair%20and%20Diagnosis/Engine%2C%20Cooling%20and%20Exhaust/Engine/Service%20and%20Repair/Engine%20Disassembly/ lemon-manuals.la — 1984 300ZX VG30ET, Engine Disassembly].

# '''FSM 1986 (OCR text of the 1986 manual; may contain OCR errors)''': EM-45, MT-32, AT-91, PD-31, BR-20, FA-24, RA-24, ST-20, MA-42. Used to confirm 1987 values and to source 1984–86 year splits.

== See also ==

* [[Z31/z31fsm_php|Z31 Factory Service Manuals]] — full FSM PDFs
* [[Z31/nuts bolts php|Z31 Nut and Bolt List]] — G-E's full measured list
* [[Z31/timingbelt php|Timing belt replacement]]
* [[Z31/basics|Z31 basics]]

== Unverified — not yet found in FSM ==

<div style="border:2px solid #c00; padding:0.5em 1em; background:#fff4f4;">
'''Warning: unverified.''' These values were on the first version of this page (2026-05-17), which was generated by a bot without citations. None of them has been found in the 1987 FSM or in the measured-size sources. They are kept here only so nothing disappears silently. '''Do not use them''' until someone confirms them against a source and moves them into the tables above with a citation. Old values that the FSM or the measured list contradicted have been replaced above and are not repeated here.
</div>

{| class="wikitable sortable"
|-
! Location (as originally listed) !! Thread (unverified) !! Torque (unverified) !! Status
|-
| Main bearing cap bolts || M11 × 1.25 || — || Thread not in any source. FSM torque is given above.
|-
| Connecting rod cap bolts || M9 × 1.25 || — || Thread not in any source
|-
| Cylinder head bolts || M11 × 1.25 || — || Thread not in any source
|-
| Camshaft bearing cap bolts || M8 × 1.25 || 13–15 lb·ft / 18–20 N·m || No camshaft bearing cap entry in FSM 1987 EM S.D.S. (the VG30E is SOHC with rocker shafts; see the rocker shaft row above)
|-
| Rocker cover bolts || M6 × 1.0 || — || Thread not in any source
|-
| Oil drain plug || M14 × 1.5 || — || Thread not in any source
|-
| Oil filter adapter || M20 × 1.5 || 12–15 lb·ft / 16–20 N·m || FSM lists "oil filter bracket" and "oil filter stud" instead (above); "adapter" value not found
|-
| Spark plugs || M14 × 1.25 || — || Thread not in any source
|-
| Intake manifold bolts || M8 × 1.25 || — || Thread not in any source
|-
| Turbo-to-manifold nuts (ET) || M10 × 1.25 || — || Thread not in any source
|-
| Turbo oil feed banjo bolt (ET) || M12 × 1.25 || 12–15 lb·ft / 16–21 N·m || FSM gives "oil feed tube" 15–20 N·m (above); a banjo bolt value was not found
|-
| Manual trans-to-engine bolts || M12 × 1.25 || — || Thread not in any source
|-
| Manual trans drain/fill plugs || M24 × 1.5 || — || Thread not in any source
|-
| Manual trans rear mount-to-crossmember || M10 × 1.25 || — || Thread not in any source. The 1986 FSM torque is given above.
|-
| Shift lever retainer bolts || M8 × 1.25 || 9–12 lb·ft / 12–16 N·m || Not found
|-
| Automatic trans drain plug || M18 × 1.5 || 22–29 lb·ft / 29–39 N·m || Not found in FSM AT S.D.S.
|-
| Torque converter-to-drive plate / converter housing bolts || M10 × 1.25 / M12 × 1.25 || — || Threads not in any source
|-
| Driveshaft center bearing bracket || M8 × 1.25 || 9–14 lb·ft / 12–19 N·m || Not found in FSM PD
|-
| Rear axle/stub shaft nut || M24 × 1.5 || — || Thread not in any source. The old note "stake after tightening" was not found for this nut (FSM RA-9 staking applies to the drive shaft serration).
|-
| Half-shaft-to-diff bolts || M8 × 1.25 || — || Thread not in any source
|-
| Brake caliper slide pins || M8 × 1.25 || — || Thread not in any source
|-
| Rear caliper bracket bolts || M10 × 1.25 || — || Thread not in any source
|-
| Brake rotor screws || M6 × 1.0 || 4–7 lb·ft / 5–9 N·m || Not found
|-
| Master cylinder to booster || M10 × 1.25 || — || Thread not in any source
|-
| Brake line fittings || M10 × 1.0 || — || Thread not in any source
|-
| Front strut top mount nuts || M10 × 1.25 || — || Thread not in any source
|-
| Front lower control arm pivot bolt || M14 × 1.5 || — || Thread not in any source
|-
| Lower ball joint nut || M12 × 1.25 || — || Thread not in any source; old note "cotter pin" not checked
|-
| Front sway bar end link / clamp bolts || M8 × 1.25 || — || Threads not in any source
|-
| Tie rod jam nut || M14 × 1.5 || — || Thread not in any source
|-
| Rear "strut-to-knuckle bolt" || M12 × 1.25 || 58–72 lb·ft / 79–98 N·m || No such entry in FSM RA (the Z31 rear uses shock absorbers and semi-trailing suspension arms)
|-
| Rear strut top mount nuts || M10 × 1.25 || 22–30 lb·ft / 30–40 N·m || No such entry in FSM RA
|-
| Rear lower arm pivot bolts || M14 × 1.5 || — || Thread not in any source. The FSM torque for the suspension arm pivot is given above.
|-
| Rear upper arm pivot bolts || M12 × 1.25 || 47–58 lb·ft / 64–78 N·m || No upper arm in FSM RA
|-
| Rear toe arm bolts || M14 × 1.5 || 69–83 lb·ft / 94–113 N·m || No toe arm in FSM RA
|-
| Rear sway bar end links || M8 × 1.25 || — || Thread not in any source
|-
| Rear crossmember bolts || M12 × 1.25 || 40–47 lb·ft / 54–64 N·m || Not found as a separate entry
|-
| Hood hinge bolts || M8 × 1.25 || 9–14 lb·ft / 12–19 N·m || Not found in FSM BF
|-
| Seat belt anchor bolts || M12 × 1.25 || — || Thread not in any source (FSM rear anchor torque is given above)
|-
| Battery terminal bolts (side post) || M5 × 0.8 || 3–4 lb·ft / 4–5 N·m || Not found
|-
| General note: "add ~10% for oiled threads" || — || — || Not found in FSM. The FSM instead says to oil specific fasteners where required (e.g. connecting rod nuts, EM-32).
|}

[[Category:Z31]]
[[Category:Reference]]
[[Category:Maintenance]]