Fixed Pins with Fitting Position Front and Rear, Front Axle, Rear Axle for MITSUBISHI TRITON ML, MN 4WD

Nolathane fixed pins replace the pin that holds the front eye of the ML, MN 4WD TRITON leaf spring to the chassis. It?s one of the most heavily loaded pivots in a leaf spring suspension, and on many 4WDs and utes it?s also one of the first to seize. Greasable fixed pins, also called greasable shackle pins or greasable spring pins, let the front eye bushes be lubricated in place, so the spring keeps pivoting smoothly and the bushes last far longer.

Fitting a greasable fixed pin is a practical upgrade for vehicles that tow, tour, work hard or regularly see water, mud, sand and dust.

What the Fixed Pin Does on the ML, MN 4WD TRITON

A leaf spring is mounted to the chassis at both ends. The rear end attaches through a swinging shackle so the spring can lengthen as it flexes. The front end is held by the fixed pin, a bolt that passes through the spring?s front eye and the chassis hanger.

The front eye doesn?t move fore and aft like the shackle end, so the fixed pin and its bushes locate the whole axle. They carry most of the braking and acceleration loads that push the axle backwards and forwards. If the pin or its bushes wear, the axle can move under load, causing rear-end steer, wander and instability, especially when towing or carrying a heavy load.

Why Factory Fixed Pins Cause Problems

Most factory fixed pins are plain bolts with no way to add grease. Over time:

• Water, dust and grit work into the gap between the pin and the bush sleeve
• The contaminants grind the bushes and the pin, causing wear and noise
• Rust forms between the pin and the sleeve
• The pin seizes, forcing the bush to twist instead of pivot
• The twisting tears the bush and makes future replacement difficult

A seized fixed pin can be very hard to remove and sometimes has to be cut out, turning a simple bush replacement into a much longer job.

How Greasable Fixed Pins Work

A greasable fixed pin has a grease fitting and internal passages that deliver grease along the pin to the bush surfaces. Pumping grease in pushes out old grease, water and dirt and leaves a fresh film where the bush pivots. The result is:

• Smoother spring articulation and a more compliant ride
• A quieter rear end without squeaks and groans
• Longer bush life, because grit is flushed out rather than ground in
• A pin that stays free and easy to remove at the next service
• Better resistance to corrosion from salt water and wet conditions

Some greasable pin kits include new front eye bushes, so the whole pivot is renewed at once. Each listing shows what?s included and the vehicles it suits.

Signs Your ML, MN 4WD TRITON Fixed Pin Needs Attention

• Squeaking or groaning from the front of the rear springs over bumps
• A clunk under braking or when taking off
• The rear of the vehicle wandering or steering itself under load
• Rust staining or corrosion around the front spring hanger
• A pin that won?t turn or can?t be removed
• Cracked, split or extruded rubber at the front spring eye

Polyurethane Front Eye Bushes

Greasable pins work best with polyurethane bushes, which hold the spring eye firmly and resist oil, grease, ozone and weathering. Nolathane has been making polyurethane suspension bushings since 1974, originally developed to replace brass bushes in hillclimb competition. The signature red bushings are made in a range of durometers (hardness grades) for each position, are mechanically fitted with minimal crush, and offer outstanding abrasion resistance and high load-bearing capability.

The honest trade-off is that polyurethane bushes need periodic greasing to stay quiet, which is exactly what a greasable fixed pin makes easy.

Protecting the Grease Fitting

Grease fittings on fixed pins sit low on the chassis, where mud, sand and stones can damage or clog them. Protective caps keep the fitting clean between services and prevent damage on rough tracks. Check that the fitting is clean and accessible before greasing, and replace any damaged fittings.

Fixed Pins, Shackles or a Complete Kit

The fixed pin is only one part of the leaf spring mounting system. For the most complete result:

• Replace the fixed pins on both sides at the same time
• Consider greasable shackles for the rear of the spring
• Replace the front eye, rear eye and shackle bushes together
• Fit new U-bolts if the springs are being removed from the axle

Renewing all the pivots at once avoids leaving a worn part to undermine the new ones.

Fitting Greasable Fixed Pins on Your ML, MN 4WD TRITON

Fitting suits professional workshops and experienced home mechanics. As a general guide:

1. Park on level ground, chock the front wheels and support the chassis securely on stands.
2. Support the axle with a jack to take the load off the spring.
3. Work on one side at a time, removing the old fixed pin, which may need to be cut out if it has seized.
4. Remove the old front eye bushes and clean the spring eye and chassis hanger.
5. Fit the new bushes with a grease suitable for polyurethane.
6. Fit the greasable fixed pin, positioning the grease fitting so it?s easy to reach.
7. Lower the vehicle onto its wheels and tighten to specification at ride height.
8. Grease the fitting until fresh grease appears, then repeat on the other side.

Tightening the pin with the spring hanging at full droop pre-loads the bushes and shortens their life, so always do the final tightening at ride height.

Greasing Schedule

Grease greasable fixed pins at every service, after beach driving, water crossings or mud, and after long trips on dusty or corrugated roads. Use a grease suitable for polyurethane bushes and pump until fresh grease appears at the joint.

Choosing the Right Fixed Pins for Your ML, MN 4WD TRITON

Confirm the vehicle, drivetrain, body style and model year, as spring eye and hanger sizes differ between variants. Our fitment guarantee means the pins you order for your ML, MN 4WD TRITON are confirmed to suit it.

Shop Fixed Pins for Your ML, MN 4WD TRITON

Fixed pins are part of Nolathane's leaf springs range, alongside leaf spring shackles for the moving end of the spring.

Find the fixed pins for your ML, MN 4WD TRITON, then order online with fast shipping or have them fitted by a Nolathane reseller. Every product is backed by Nolathane?s warranty, 60-day returns give you time if a part isn?t right, and our local support team can help whether you?re freeing up a seized rear end, servicing a working ute or preparing a 4WD for touring.