Nissan Terrano WD21 is a legendary SUV that is still popular due to its reliability and cross-country ability. However, even this “tank” is not immune to rust, especially in the rapids area. Corrosion not only spoils the appearance, but also threatens safety: rotten sills reduce the rigidity of the body, which can lead to deformation in an accident or off-road.

In this article we will look at everything you need to know about thresholds for Terrano WD21: from the selection of original and analog parts to step-by-step instructions for replacement and anti-corrosion treatment. We will also tell you how to temporarily protect thresholds if a complete replacement is not yet affordable, and what mistakes owners most often make during repairs.

Original vs. universal thresholds: what to choose for Terrano WD21

The first question that faces the owner is whether to buy original sills from Nissan or find analogues. Original parts, of course, fit perfectly in geometry, but their price can reach 15–20 thousand rubles per set (excluding work). In addition, they cannot always be found in stock, especially for rare modifications.

An alternative is universal thresholds from third-party manufacturers (for example, Febi, Meyle or domestic brands). They are cheaper (from 3-5 thousand rubles per pair), but it is important to consider:

  • 🔧 Metal thickness - for cheap analogues it is often smaller than for the original (0.8–1 mm versus 1.2–1.5 mm).
  • 📏 Compliance with body shapes — universal thresholds may require local adjustment.
  • 🛡️ Protective coating — some analogues already come with zinc coating, which simplifies anti-corrosion treatment.

If your budget is limited, you might consider used original thresholds from the showdown. The main thing is to check them for hidden corrosion (especially in places of welds) and the presence of traces of previous repairs. The price for such parts is usually 2-3 times lower than new ones.

📊 Which thresholds do you prefer for Terrano WD21?
  • Original new
  • Universal analogues
  • Used original
  • Homemade from sheet metal

When is it time to change thresholds: signs of critical corrosion

Many owners Terrano WD21 They've been driving with rusty sills for years, not realizing that it could be dangerous. Here are the key signs that it’s time for urgent repairs:

  • 🚨 Through holes - even small (1–2 cm in diameter) holes in the lower part of the threshold indicate deep corrosion.
  • 🔩 Paint peeling and blistering - if the metal makes a dull sound when tapped, this means that the rust has already “eaten” it from the inside.
  • 🚗 Door deformation — if the doors begin to close poorly or distortions appear, this may be a consequence of weakened thresholds.
  • 💧 Constant moisture in the cabin — rusty thresholds often cause leaks during rain.

Particular attention should be paid places where the thresholds are attached to the side members. If rust appears here, the body can lose up to 30% of its rigidity, which is critical for an SUV. You can check this by pressing the threshold with your hand: if it bends or makes a creaking noise, it’s bad.

⚠️ Attention: If the sills are rotten to such a state that when pressed with your foot the metal is pressed through, driving such a car is dangerous! In the event of an accident, the body can collapse like a house of cards.

Step-by-step instructions for replacing thresholds on Terrano WD21

Replacing thresholds is a labor-intensive process that requires welding and metal working skills. If you have never held a grinder or welding machine in your hands, it is better to entrust it to professionals. However, if you decide to do it yourself, here are detailed instructions:

Place the car on a level surface and secure the wheels

Disconnect the negative battery terminal

Remove the doors (if necessary) and upholstery in the sill area

Protect the windows and body with cardboard or film from sparks

Prepare a new threshold, try it on before welding-->

  1. Removing the old threshold

    Using a grinder, carefully cut off the welds securing the threshold to the body. Start from the bottom, gradually moving to the side members. Don't cut the body! - only seams. If the threshold is welded with an overlap, cut it flush.

  2. Surface cleaning and preparation

    Remove the remnants of the old threshold, clean the rust down to “living” metal (you can use a metal brush or sandblast). Treat the surface rust converter (For example, Tsinkar) and degrease.

  3. Fitting and welding of a new threshold

    Attach a new threshold, check the alignment of the holes and gaps. Start tacking it by spot welding in 3-5 cm increments, then weld the seams with a continuous seam. For reliability, you can additionally use rivets at the points of attachment to the side members.

  4. Anti-corrosion treatment

    After welding, clean the seams and apply primer for metal and paint the threshold in the body color. Be sure to treat the internal cavity of the threshold anticorrosive (For example, Movil or Dinitrol) through technological holes.

If you don’t have welding skills, you can use riveted sills (for example, from AvtoVAZ for Niva). They are attached with rivets and sealant, but this option is less reliable and is only suitable for temporary repairs.

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Apply to joints before welding welding primer (For example, Loctite 7610) - this will protect the metal from oxidation and improve the quality of the seam.

Anti-corrosion treatment: how to protect thresholds for a long time

Even new thresholds without proper protection will quickly begin to rust. In the case of Terrano WD21 it is especially important to pay attention internal cavity of thresholdswhere moisture and dirt constantly get in. Here are proven methods of protection:

Processing method Benefits Disadvantages Protection period
Movil/Cannon fat Low price, easy application, good moisture protection Washed off after 1–2 years, requires regular updating 1–3 years
Liquid plastic (Dinitrol ML) Does not dry out, does not crack, protects against mechanical damage Dear, difficult to apply without a sprayer 3–5 years
Zinc plating Maximum protection, chip resistant Requires special equipment, high price 5–10 years
Anti-gravel film Protects against chips and scratches, you can glue it yourself Does not protect against corrosion from the inside, may peel off 2–4 years

For maximum protection, it is recommended to combine methods. For example:

  1. Process the internal cavity of the threshold Movilem through technological holes.
  2. Apply to external surface liquid plastic or anti-gravel.
  3. Paint the threshold in the body color with preliminary priming.
⚠️ Attention: Never use on thresholds bitumen mastic! It cracks over time, accumulates moisture and accelerates corrosion.

Temporary solutions: how to extend the life of thresholds without replacement

If completely replacing the thresholds is not yet affordable, you can temporarily slow down corrosion in the following ways:

  • 🔧 Fiberglass patches - Suitable for small through holes. Glue the fiberglass fabric with epoxy resin on the inside and outside, then putty and paint.
  • 🛠️ Homemade pads — cut out of sheet metal (1–1.5 mm thick) linings in the shape of the threshold and screw them onto self-tapping screws with sealant.
  • 🧴 Rust converter + primer - remove rust, treat Tsinkarem, then apply primer and paint. This will not stop corrosion, but it will slow it down by 1-2 years.

Another option - installation of plastic covers (for example, from Niva Travel). They do not protect against rust, but prevent mechanical damage from stones and dirt. Such overlays cost about 2–3 thousand rubles per set.

What happens if you ignore rusty sills?

Rotten thresholds lead to:

1. Loss of body rigidity — in an accident or off-road conditions, the body can deform unpredictably.

2. Leaks into the interior — water will enter through the holes, which will lead to rust of the floor and electronics.

3. Problems with doors — body distortions can make it impossible to open/close doors normally.

4. Problems during maintenance — through corrosion of thresholds is a reason for refusal of technical inspection.

Typical mistakes when repairing thresholds and how to avoid them

Many owners Terrano WD21 They are faced with the fact that after self-repair, the thresholds rust even faster. Here are the most common mistakes:

  • 🔥 Welding without metal protection - if not used welding primer or zinc spray, the seams will begin to rust within a few months.
  • 🧽 Poor rust removal — if corrosion is not removed to the “living” metal, it will continue to spread under the new coating.
  • 🎨 Painting without primer — paint applied directly to metal will peel off quickly. Be sure to use epoxy primer.
  • 🚫 Ignoring the internal cavity — many people treat only the outer side of the threshold, forgetting about the inside, where corrosion develops more actively.

Another common problem is incorrect choice of metal thickness. If the new threshold is thinner than the original one, it will not withstand the loads of off-road driving and will quickly deform. Optimal thickness for Terrano WD21 — 1.2–1.5 mm.

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The most common cause of rapid corrosion after repair is the lack of treatment of the internal cavity of the threshold. Even if the outside is perfectly painted, moisture inside will continue to destroy the metal.

Where to buy thresholds for Nissan Terrano WD21: trusted suppliers

Find quality thresholds for Terrano WD21 possible in the following ways:

  • 🏆 Official Nissan dealers - original parts, but high price and long delivery times (if the part is made to order).
  • 🔧 Specialty stores:
    • Exist.ru - large selection of analogues from Febi, Meyle.
    • Autodoc.ru — there are often discounts and promotions.
    • Emgrand.ru — specialize in spare parts for Japanese SUVs.
  • 🔄 Showdown — used original thresholds can be found at Avito, Drom.ru or in local disputes. The main thing is to check for hidden rust.
  • 🛠️ Homemade thresholds — if you have access to a bending machine, you can cut the thresholds from sheet metal according to a template.

Be sure to check when purchasing year of manufacture And modification your Terrano WD21, since the thresholds for restyled models (after 1996) may differ in fastenings.

Threshold prices for Terrano WD21 (for 2026):

  • Original new: 15,000–25,000 rub. per set.
  • Universal analogues: 3,000–8,000 rub. per set.
  • Used original: 5,000–12,000 rub. per set.

FAQ: Frequently asked questions about thresholds on Nissan Terrano WD21

Is it possible to drive with rusty sills if the holes are small?

Technically possible, but highly undesirable. Even small holes grow over time, and corrosion spreads to the side members. If your budget is limited, at least fill in the holes. fiberglass on epoxy and process Movilem.

How long does it take to replace thresholds?

Service time: 1–2 days (depending on the degree of corrosion). Do it yourself - from 3 days to a week, if you do everything carefully and with anti-corrosion treatment.

Which welding is better to use: semi-automatic or inverter?

For thresholds Terrano WD21 better semi-automatic (MIG/MAG) - it gives a more accurate and durable seam. Inverter (manual arc welding) is only suitable for experienced welders, as there is a high risk of burning through the metal.

How to check if the thresholds are rotten from the inside?

Take screwdriver or awl and pierce suspicious areas (for example, under plastic plugs). If the tool goes in easily, the metal has rotted. You can also use endoscope to inspect the internal cavity.

What should I do if, after replacing the thresholds, the doors do not close well?

This means that the body was deformed during welding. Need:

  1. Check the geometry of the sills and side members.
  2. If necessary, adjust the door hinges.
  3. If the deformation is severe, contact a bodybuilder for straightening on the slipway.