Nissan Patrol Gearbox & Transmission Problems

Loss of fifth gear was a problem that did occur with some Patrols, and Nissan was covering at least part of the cost to repair some of them when they were newer. Yours is now coming up for 13 years old and I doubt you would have any chance of getting the company to cover the cost of repairing it, even though you have done relatively few kilometers. If you feel you want to pursue it you might be able to get part compensation for the cost of repairs.

Towing in overdrive really loads up the transmission, so you have to think about how you use it. Generally it is ok to engage overdrive on flat terrain, where the load is not as high, but it's important to disengage it when facing hills. The key is to always be in the correct gear for the situation, rather than leave it in overdrive and forget about it.

If your can manually force the shift then there’s probably nothing wrong with the actual gearbox and its mechanicals. Instead, the problem is likely to be an electronic one, perhaps with the speed sensor that tells the computer the car’s road speed and tailors the gearshifts to reflect that. Don’t forget, however, that gearboxes like the Nissan’s with many gears, often won’t select higher gears at low speeds. So if the car refuses to select sixth or seventh gear at urban speeds, that’s possibly just the calibration Nissan has fitted to it.

If this is an actual problem (and not just a characteristic) this is a very new vehicle and would be covered for this sort of problem by the factory warranty.

This mightn’t be too hard to figure out as the GU Patrol used a purely mechanical engagement system for the transfer case and four-wheel-drive system. Unlike newer designs with rotary knobs and electronic control, there’s really not to much to go wrong with the Patrol’s setup assuming it’s a selector problem. Make sure the selector rods are all connected properly and that they’re not binding or loose under the car.

However, if the lever is engaging and the front drive-shaft is not turning the front wheels, then you may have a hub problem. Free-wheeling hubs are great for saving fuel, but when they go wrong, it can often mean the drive doesn’t reach the front wheels. At that point, you have a bigger job on your hands. The same symptoms could also be a result of a broken front differential which is not sending the drive out to the front wheels. Finally, the transfer-case itself may be at fault. If it’s not sending the drive forward, there’s no way the vehicle will achieve four-wheel-drive.

Also, to maximise your chances of engaging four-wheel-drive, make sure the vehicle is stationary at the time and the transmission is in neutral. In fact, this is essential for moving between two and four-wheel-drive in many types of off-roader.

You would expect it to be revving harder with the extra load of the trailer on the back, so that’s normal. I would engage overdrive when conditions suit, like on the flat, and run at the lower speed, but disengage it when the engine starts to labour, such as climbing hills or pushing into a head wind etc.

Nissan spokesman, Peter Fadeyev, replies: "Nissan replaced the diff-lock solenoid and diff-lock actuator on Mr Antoney's vehicle under its New Vehicle Warranty. More than 18 months later the customer sought a replacement differential but the problem was not due to a manufacturing fault so it was not repaired or replaced by Nissan. As the original differential problem was not repairable under the terms of his car's warranty, and the replacement differential was a second-hand unit and not replaced by an authorised Nissan workshop, Nissan is unable to reimburse Mr Antoney for its cost".

Without knowing the cost of labour in Qatar the cost seems about right if you’re going to replace the transmission.

Carmakers, and it appears Nissan in particular, choose to hide behind their warranties, which exclude wear and tear items. But I believe you could argue that the extremely short clutch life that many people are experiencing with vehicles fitted with dual-mass flywheels makes them unfit for purpose under our consumer laws. Something needs to be done. Perhaps you could get other owners to join you in an approach to Nissan on the problem.

You could be looking at something internally wrong with the transmission, but the clue that this might be something simpler is in the way the engine will start in Reverse which, of course, it shouldn’t (for safety reasons). The suspicion would be that the relationship between the selector (inside the cabin) and the actual gearbox is somehow out of synch. So when the selector is telling you the car is in Reverse, it’s actually in Park or Neutral, which is why the engine will start.

That might also explain why the car won’t select fourth gear; the position that actually coincides with Drive (or fourth gear) looks – from inside the cabin – to be the Neutral position. So, to check this, put the car in what looks like Neutral and, in a safe place, see if it moves when you give it some throttle.

Failing that, you’ve got two separate problems. The first is the inability to select fourth gear (which could be a hundred things) and a failure of the safety switch which is allowing the engine to start in Reverse.

You could be dealing with either a worn transmission itself (where wear inside the gearsets, shafts or torque converter has made something sloppy) or there’s something else in the driveline (such as a differential or universal joint) that has likewise allowed some looseness or play to enter the equation. In either of those cases, a thump or clunk during shifts can be a symptom. It feels worse under acceleration, as that’s when the maximum stress is on all those moving, meshing parts.

Sometimes, a transmission can be serviced and adjusted to get rid of thumping or banging during shifts. Take the car to a transmission specialist who will be familiar with this transmission and may be able to return it to civility.