Td5 vs TDCi: which Defender engine to live with
The last two Defender diesels split every owner. We put the five-cylinder Td5 and the Ford-era TDCi side by side on reliability, running costs and the drive itself.
The full-fat Range Rover rides like nothing else — until it doesn't. The honest cost of fixing air versus going to springs.
The L322 Range Rover rides like a magic carpet right up until a compressor gives out on a cold morning and the dash lights up with "suspension fault". At that point every owner faces the same fork in the road: repair the air system properly, or convert to steel coil springs and be done with it. Both are valid — but only if you know what each one really costs.
Age is the enemy. The rubber bags perish and split at the folds; a small leak makes the compressor run more, and an overworked compressor wears out and burns its relay. The valve block and O-rings dry out and leak too. It is rarely one big failure — it is a chain of tired parts, and fixing only the loudest one is why some cars visit three times.
Done once, done right means genuine or quality OEM bags on all four corners, a new or rebuilt compressor with its dryer, and a fresh valve block if the old one leaks. It is not cheap, but the reward is the ride and the load-levelling that made you want the car in the first place — and a system that then behaves for years rather than months.
A coil-conversion kit is cheap and ends the fault lights for good, which is genuinely tempting. But you lose ride-height control, automatic load levelling and the raised off-road setting — on a two-tonne luxury car that is a real downgrade in both comfort and capability. On a high-mileage car you plan to keep cheaply it can make sense; on a good one it is a shame.
On the early BMW-era 3.0 diesels the air hardware is simpler and cheaper to source than on the later cars — worth checking which generation you have before you write off a repair as uneconomic.
Fix the air on a car worth keeping; convert the one you just need to keep moving.
Ivan Petrov · Master Technician
Book it into the Ram Parts workshop, or order the parts and do it yourself — either way you get the same advice.