Classic Transmission

16/08/2026

The usual S10 NWC T5 problems + SBC input conversion

The owner bought this gearbox expecting it to be in good condition, unfortunately it had the usual problems. Because the input was damaged it made sense to also do the Small Block Chev conversion which reduces the length of the input and front bearing retainer.

S10 T5 gearboxes are a popular choice for hot rod builds due to the shifter location and slim case. Also as the T170 gearboxes are getting harder to find for the Ford builds these are usually the go to.

15/08/2026

FWD Honda gearbox (T2W4) from CL1 chassis with H22A engine.

Recently we got asked to look at a T2W4 gearbox, they usually come apart quite easily so I decided to stripe down the gear train onsite so the owner could immediately see the problems.

Surprisingly it wasn’t just synchro ring and dog teeth damage from a bad clutch but also water damage.

Luckily the inside roller surface of the gears could be honed (last two images) and the gears / hubs dog teeth repointed.

15/08/2026

Winning the NWC S10 T5 lottery & some shimming basics

Finding a used Non World Class S10 T5 gearbox that hasn’t worn through the roller surface on the Mainshaft is a very rare find, this one only needed new bearings, new synchro rings and repointing dog teeth.

Correctly shimming a T5 is important, for checking the input + mainshaft I leave out the input seal and 4th synchro ring because of the drag they create.

On a NWC T5 it also pays to check the front to back clearance on the cluster shaft and the placement of the center roller.

Hopefully this info may benefit some of you.

16/05/2026

FORD 3+OVERDRIVE - the perfect solution in a fuel crisis

Instead of 4th being 1:1 like the earlier Toploader , this gearbox makes 3rd 1:1 allowing 4th to be an overdrive gear.

This allows you to go faster and also gives more fuel economy on the highway as you won’t have to rev so high.

These were being used in Ford Mustangs before the T5 came along.

26/04/2026

Tremec TUET7000 , part of the T56 evolution towards TR6060

01/04/2026

T56 - preventative fix

This gearbox was designed for America’s muscle cars and it fit the requirement perfectly. However Holden and Aussie Ford fitted it to family saloons and utes which often pulled heavy loads for prolonged periods.

A common failure I used to see in the Commodore and Falcon T56 gearboxes was the thrust collar behind 6th gear welding to the bearing. The loaded gear would press hard against the collar spinning it on the bearing without any oil getting in between the two parts. The collar would start to weld and as both collar and gear expanded with the excess heat the gear would also start to fuse.

As you go through the images you’ll see the original part , where it sits in the assembly and then the modified part. This surprisingly simply fix made a huge difference.

31/03/2026

FOR SALE - listed on trademe

Holden V8 M20 Gearbox - Rebuilt 4 speed

10 gearboxes came apart to provide the best gears , hubs and synchros available.

New: Input shaft , Heavy Duty Front Bearing Retainer , Bearings and Seals.

This runs a 3.05 first gear ratio , so it's very close to the 2.95 ratio used in the VN-VS T5 and T5G (VK-VL). This shares the same driveshaft and mounting points as the trimatic auto transmission so it is an easy conversion.

Will fit behind 253 , 308 and 304 engines.

26/03/2026

23/03/2026

Return to the world of Cobra

Recently we made a house call to ensure the clutch setup was clearing completely when the pedal was depressed. This check needs to be performed on all cars that have had drivetrain changes, aftermarket clutch component installs, manual conversions or are suffering from poor gear shifting.

This particular Cobra replica benefits from an LS1 engine and 6spd Tremec gearbox. Carbon fibre replaces the traditional chrome and wood grain giving it a modern feel.

I say return to the world of AC Cobra because a long time ago I worked for a transmission workshop run by a Cobra enthusiast who headed the club so plenty of these cars in their many forms crossed my path regularly over that nearly 14 year period.

11/02/2026

RACE CAR REPAIR: one of Brock’s specials.

Recently we repaired a Holden M21 from one of the 30 special edition VH Commodores that GMNZ asked Peter Brock to help produce at their Trentham plant.

GMNZ wanted to win the Benson and Hedges racing series and homologation rules of production car racing at the time required that a minimum of 25 units had to be assembled. 29 white cars and 1 black (for the GMNZ manager) were built.

Because Brock could strip out the pollution equipment in New Zealand unlike Australia law requirements the output of these cars could exceed what he was working on over the ditch.

This particular Holden 4 Speed had blown teeth on 4th , however the wear from racing causing the geartrain to thrust back and forth under load was evident so we had to replace a few more parts than normal.