Healey Top Trunnion Bearing Upgrade

Top Trunnion Bearing Upgrade for Austin Healey & Sprite Steering

Posted: Tuesday, 7 April 2026 @ 15:59

Austin Healey heavy steering turning front wheels workshop scene

Why Your Healey Steering Feels Heavier Than It Should

If you’ve ever wrestled with your Austin Healey or Sprite at low speeds, you’ll know the feeling. Parking becomes a forearm workout, tight manoeuvres feel reluctant, and the steering never quite feels as precise as you’d like.

In many cases, the culprit isn’t worn racks or geometry. It’s the humble top trunnion thrust washer quietly doing its best with 1950s thinking.

worn bronze thrust washer from Austin Healey top trunnion showing friction wear

The Problem:

Bronze Thrust Washers Create Friction

The original setup relies on a bronze thrust washer (2A4006 on Sprite/Midget), which works… up to a point.

But over time, and especially under modern driving conditions:

Friction builds at the pivot point
Steering effort increases
Wear accelerates
Feedback becomes vague

It’s a design that made sense when tyres were narrower and expectations lower. Today, it’s one of the biggest hidden causes of heavy steering.

Austin Healey top trunnion needle roller bearing kit replacing thrust washer

The Solution:

Needle Roller Bearing Conversion

Replace that sliding friction with rolling motion, and everything changes.

Both of these kits do exactly that:

Each kit replaces the original thrust washers with a properly engineered bearing assembly, removing one of the biggest sources of friction in the front suspension. One kit covers both sides of the car, so you’re not chasing extra parts halfway through the job.

comparison of bronze thrust washer and needle roller bearing kit for Healey steering upgrade

What Difference Does It Actually Make?

Quite a lot, frankly.

Key Benefits at a Glance

Noticeably lighter steering
Especially when parking or manoeuvring
Reduced friction at the pivot point
Needle rollers replace sliding contact
Improved steering feel and accuracy
Less resistance, more feedback
Stronger, longer-lasting components
Hardened materials outperform bronze washers
Better suited to modern use
Wider tyres and increased castor benefit most
Complete kits supplied
Includes washers and shims where applicable

Is It Worth the Effort to Replace the Thrust Washers?

Short answer: yes. Longer answer: you’ll wonder why you didn’t do it sooner.

In reality, the work involved is largely the same as replacing standard thrust washers. You are already dismantling the top trunnion assembly, so fitting the bearing kit is simply doing the job properly rather than putting the same limitation straight back in place.

The effort is in getting access, not in the upgrade itself. Once you’re there, the difference in outcome is significant.

This is one of those rare upgrades that:

Doesn’t alter the character of the car
Doesn’t introduce complexity
But makes every drive noticeably easier and more enjoyable

Even moving cars around the workshop at walking pace, it’s immediately obvious which ones have had the conversion… and which haven’t.

needle roller bearing detail used in Austin Healey top trunnion upgrade kit

Technical Insight:

Why Bearings Work Better

A bronze washer relies on sliding friction. Even when lubricated, there’s resistance.

A needle roller bearing uses rolling elements, which:

Reduce contact friction dramatically
Distribute load more evenly
Maintain consistent movement under load

Add hardened, ground washers into the mix and you’ve effectively created a proper bearing race where there wasn’t one before.

It’s a small engineering change with a disproportionately large effect.

Choose your top trunnion bearing kit

If you’re tired of heavy steering or already working on the front suspension, this is one of the most worthwhile upgrades you can make. Both kits are supplied as pairs, so one kit is enough to replace the thrust washers on both sides of the car.

The result is immediate. Lighter steering at low speeds, smoother response through corners, and a front end that feels far more precise and willing. It’s the sort of change you notice the moment you pull out of the drive.

The Result: A More Enjoyable Drive

The result is a Healey that feels lighter in your hands, more responsive through every corner, and genuinely more enjoyable to drive every time you get behind the wheel

Where low-speed manoeuvres once felt heavy, the car now turns in with ease. Out on the open road, the steering feels smoother, more precise, and far less of a fight.

Austin Healey driving through English countryside smooth cornering improved steering

Frequently Asked Questions

Do I need any additional parts when fitting this kit?

No. The kits are designed as complete solutions. Big Healey kits include shims, and everything required for installation is supplied.

Do I need one kit per side or per car?

Each kit is supplied as a pair, which is enough to replace the thrust washers on both sides of the front suspension.

How does a needle roller bearing improve steering?

A needle roller bearing replaces sliding friction with rolling motion. This significantly reduces resistance within the trunnion, resulting in lighter steering, smoother movement, and improved feedback through the steering wheel.

How long do needle roller bearings last compared to bronze thrust washers?

Needle roller bearings are designed for reduced wear and longer service life. With proper installation and lubrication, they significantly outlast traditional bronze washers.

Is fitting a top trunnion bearing kit difficult?

If you are already comfortable working on front suspension components, the upgrade is straightforward. The bearing kit installs in place of the original thrust washers, so no major modifications are required.

Is it worth upgrading if my thrust washers are not worn out?

Yes. Even new bronze washers still rely on sliding friction. The bearing conversion reduces that friction from the outset, so the improvement is present regardless of wear.

Is this upgrade suitable for cars with wider tyres or modified suspension?

Yes. In fact, the benefits are often greater on cars with wider tyres or increased castor, where steering loads are higher.

What causes heavy steering in an Austin Healey or Sprite?

One of the most common causes is friction within the front suspension, particularly at the top trunnion where the bronze thrust washer operates. As these washers wear, friction increases, making low-speed steering noticeably heavier.

What does the top trunnion thrust washer actually do?

The thrust washer sits within the top trunnion assembly and allows the suspension upright to rotate as you steer. In the original design, this relies on sliding contact, which naturally creates friction and wear over time.

Will this affect the originality of my car?

No visible changes are made, and the upgrade sits within the existing assembly. It improves how the car drives without altering its appearance or character.

Will this upgrade make a noticeable difference on a standard road car?

Yes. The biggest improvement is felt at low speeds, such as parking or manoeuvring. Even on a standard car, the reduction in steering effort is immediately noticeable.

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