The Kalyani M4- All You Need To Know

Adreesh Ghoshal
6 min readAug 31, 2020

The Kalyani Group pavilion at the DefExpo 2020 had a huge armored personnel carrier take center stage.

It’s called the Kalyani M4, and some news reports suggest that the Indian Army is eyeing it keenly. Partnered with the Tata Kestrel, the Kalyani M4 makes an interesting combination of armor and speed. While the Kestrel provides the armored punch that spearheads an assault, the M4 will back it up with its speed, maneuverability, and ease of maintenance.


But, before we get into why the M4 is such an interesting vehicle, let’s clear a couple of things first. One — it’s called the Mbombe 4, and is built by the Paramount Group, a South African company that’s built and sold the Mbombe family of vehicles to quite a few international clients by now

Two — the Mbombe 4 is the smallest in the Mbombe family, which also includes the Mbombe 8 and Mbombe 6, packing much heavier firepower compared to the Mbombe 4.

Here’s what we know so far

  1. The M4 is designed as an armored personnel carrier with a higher emphasis on performance and crew protection.
  2. It can carry a maximum payload of 2.3 tons or a crew of up to eight.
  3. The 16-ton vehicle has an impressive 43-degree approach angle and a 44-degree descent angle — the world’s best off-roaders can manage up to 35 degrees approach and 28 degrees descent

4. The hull is of a monocoque type, which means that it’s an armored shell with everything installed inside of it.

5. The forward crew cab is fitted with a large two-piece windshield, which offers a clear view of the surroundings to the crew, enhancing situational awareness, while a ramp at the rear end makes ingress and egress of dismounted troops easy.

According to Defence Decode, the fording depth is 900mm.

6. Think of a very strong, armored egg, and that’s what the M4 is like.

7. The viewports are made of glass hardened enough to withstand sniper and anti-materiel rifle fire.

8. The M4 is powered by a turbocharged six-cylinder diesel engine of yet unknown displacement with a power rating of 347 kW(465hp) and 1627 Nm( 165 kg-m).

9. The numbers alone make it at least twice as powerful as other similar vehicles currently used in the Indian Army.


10. This powertrain layout gives it impressive performance; the top speed is 140 kph, with a maximum range of 800 km

11. The engine and power transfer unit are located along one straight line running through the center of the chassis, as this eliminates the use of an off-set driveline used in many four-wheel-drive vehicles.

12. The linear layout reduces the number of torque-transmission devices like shafts and torque convertors, in turn reducing transmission loss, and increasing mechanical efficiency.

13. This has the drawback of the one single drive-line unit being vulnerable to stress fractures, but we’re sure that Kalyani’s steel expertise will come in play here.


14. The automatic transmission used will most probably be of an automotive cross-drive-type combined with a CVT, meaning that in situations where a low-range or low gearing is required, a shifter may be needed.

15. When on the highway or a flat surface, the continuously variable mechanism can be used


16. This is also quite like the P R N D L set up used in passenger cars (Park, Rear, Neutral, Drive, Low) (Renk and Allison make some of the world’s best transmissions for the military, but chances are that this, too will be from an Indian supplier)

17. There are many advantages to using automotive parts for the M4, the biggest one being the ease of maintenance.

18. The differential locks are air-operated, and there are three such units.

19. The use of air also makes it more robust as electronically-locked differentials are quite expensive, although they last much longer (less moving parts = longer life).

20. The braking is primarily via disc, with pneumatic actuation and ABS in an emergency.

21. Anti-lock brakes are a safety feature that will go a long way in preventing accidents on public roads during urban operations.


22. The M4 rides on 16–00 R20 tires, which translates to rim diameter of 20 inches, and 16–00 is a size that’s standard on high-performance off-road trucks, especially those used to race in the Dakar Rally.

23. Michelin’s XZL series is a commercially-available example and they also happen to be the same variant used for the M4.

24. The tires are reinforced with run-flat inserts that can maintain tire shape and a certain degree of handling response even if they’re shot.


25. Tyre pressure is maintained using a central tire pressure inflation system that pumps air when the vehicle is fully loaded and releases it on broken/unpaved stretches to improve braking.

26. Crew comfort is also taken care of with the help of a powerful, 16kW air-conditioning system with HEPA filters to keep the crew safe in a CRBN environment

27. Here are some of the other features the M4 comes with


28. The M4 features some of the highest protection levels in its class


29. It’s rated at STANAG 4569 Level 3 for the engine compartment and similar ballistic protection for the crew compartment.

30. For STANAG 4569 Level 3 compliance, the tested compartment must resist penetration from 7.62×51mm AP (WC core, armor-piercing round) at 30 meters with 930 m/s and an 8 kg (explosive mass) anti-tank mine.


31. The entire body is rated at STANAG 4569 Level 4a and 4b, and can withstand a 50kg blast of TNT from the sides.

32. This means that the M4 can withstand fire from a 14.5×114mm AP / B32 (machine gun with armor-piercing rounds) at 200 meters with 911 m/s and a 10 kg anti-tank mine-type explosive mass

33. One thing to be clear is that the explosives are detonated both under the belly and each wheel.


34. This is along with a 155-mm shell detonated at a 60 m distance for Level 3 and a 25 m distance for Level 4 standards.

35. At the DefExpo, the M4 was seen fitted with a 12.7 machine gun with a shield for the operator.

36. Since the vehicle does not feature a dedicated turret, there’s not much left to play with in terms of offensive weaponry.

37. If we’ve got it right, it’s not designed to lead a fight, but rather serve as a backup, more like a left-winger than a mid-fielder in football.

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Adreesh Ghoshal

Automobile Engineer. Content Writer. Biker. Defense Enthusiast. Indian.