The famous London taxi has been given a makeover centred around a new Euro IV-emissions standards-compliant 2.5-litre diesel engine.

Maker LTI Vehicles claimed the latest TX4 - distinguished by a new nose - is the first purpose-built taxi to have a Euro IV compliant diesel engine. This was specially developed by VM Motori, which is owned 51% by the Penske Corporation and 49% by DaimlerChrysler. Two new transmission options, manual and automatic, have been introduced and anti-lock brakes are now standard.

On the road prices in the UK range from GBP26,995 to GBP35,495. Four trim levels are available.

Other changes include that re-styled front end, a distinctive new mesh grille, uprated all-round coil spring suspension and a general upgrading of the interior specification and level of comfort for the driver and passengers.

LTI said the new TX4 was so named as a tribute to its first purpose built 'hackney carriage' taxi, the FX4, launched in 1959.  The name is also in line with the use of a new Euro IV compliant diesel engine and for this reason LTI chose not to use the TXIII title.  The new range replaces the TXII models introduced in 2002.

LTI Vehicles managing director Peter Shillcock said: "We have invested three years and over GBP5m in bringing the TX4 to market.  We are committed to continually improving our taxis and the development of the TX4 has undergone more component and road testing than anything we have ever built. Over one million kilometres (600,000 miles) of trials have taken place, equivalent to 30 times around the world, and this has included nearly 5,000 kilometres (3,000 miles) over pave cobbled road surfaces. The TX4 has been proved in real-life extreme hot and cold climates as well as simulated conditions using the wind tunnel at MIRA (the UK's Motor Industry Research Association)."

Sales and marketing director Matthew Cheyne noted: "We have moved away from using a Ford sourced diesel engine such as the unit we used for the outgoing TXII.

"There are several reasons for this. Seventy percent of our customers specify an automatic transmission and the new VM engine comes complete with such a unit which is specifically compatible for use with their latest Euro IV engine. The same compatibility applies to the manual transmission."

"The Italian VM Motori company produces engines for markets and manufacturers around the world, including Chrysler and LDV. Since our taxis are now sold to world markets we needed to change to a world engine."

He added, "The engine mapping has been configured to supply maximum torque at low speeds for quick acceleration and improved flexibility across a wide power band for optimum performance in traffic and on the open road, all with the lowest possible emissions and fuel consumption. This engine is cleaner and quieter than the previous power units used with no loss in power or performance. The engine can also use 5% bio-diesel mix without modification.

"Another reason for switch to VM is the fact that a Ford unit was not suitable for fitment to our new TX4 left hand drive models, so again this meant a change of engine supplier."

Coventry-based LTI Vehicles is now the largest British owned independent motor manufacturer.

Earlier this month, parent company Manganese Bronze Holdings announced it had signed a Heads of Terms agreement with Chinese car manufacturer Zhejiang Geely Holding Group to establish a GBP53m joint venture company to produce the London black cab in Shanghai for the Chinese market. From mid-2008 the joint company will produce 20,000 units for sale in China and there is the possibility of supplying some Chinese sourced components to LTI in the UK.

Manganese Bronze said that LTI's full year 2005/06 pre-tax profit rose 29% to GBP3.67m.

LTI employs around 400 staff and produces nearly 3,000 taxis a year for the UK and 35 export markets. Since the company built its first Austin-based taxi in 1948, it has made over 100,000 vehicles.