hi everyone,just want to know what the RD28's are like are they really gutless are they reliable (I'm not looking to break any land speed records).what are they like in GQ or GU are they the same motor if anyone can help that would be great.
Edited by on 02-06-2008 18:21
The RD28 is the diesel version of the nissan RB engine series.
It has a cast iron block, alloy head and single overhead cam.
The only real difference between GQ and GU was the addition of a small top mount intercooler on the GU. From memory, the GU RD28 also got basic electonic controls on the injector pump where the GQ had a straight mechanical pump. Corrosion of the alloy head can be an issue if the cooling system has not been properly maintained.
GQ power figures; 85kw@4400rpm and 235nm@2400rpm
GU power figures; 95kw@4000rpm and 252nm@2000rpm
and just for comparison
GQ TD42 85kw@4000rpm and 264nm@2000rpm
The RD28 relies on the turbo to make decent power, and as such lacks power and torque off boost. To help compensate for the lack of power/torque, Nissan fitted RD28 equipped patrols with a 4.6:1 diff ratio , much shorter than the 3.9:1 fitted to TD42 Patrols. The actual diffs and axles are the same size, as is the transfer case. RD28 Patrols were fitted with a smaller alloy case gearbox (apparently out of a 300ZX), instead of the big cast iron gearbox fitted behind the bigger engines. I don't know of any durabillity issues with the gearbox, the engine didn't have enough torque to stress them that much.
The RD28 is best suited to around town and highway driving, where the short diff ratio's keep the engine spinning above 2500rpm, allowing the turbo to spool up quickly. Under these conditions, the RD28 is more economical than the TD42.
If you plan to tow anything heavier than a box trailer, or do any bush or beach (especially soft sand) driving, then I wouldn't consider an RD28.
The RD28 is not a bad engine, just a small one in a big car.
And has a much better reputation than the ZD30.
Tony
Edited by on 03-06-2008 10:32
Hi Tony thanks for your input it has been a great help I am actually buying a patrol because I need the 7 seats (and I aint driving around in a torago.)I will be using it mainly around town but when I want I can take it to the beach.I didn't think they would be very ballsy but I don't think the TD42 price range is the greatest. thanks. Aaron.
I work with a girl that purchased from a 4x4 sales yard in the Coopers Plains area, a GU with the RD28 about a year ago.
She was very happy with the fuel economy of the RD28 Engine in the GU for about 10 months.
Then the engine just stopped on her one day. When advised the engine was stuffed she was glad they paid for the extra warranty at the time of purchase.
Final Engine repair quote just over $12000.00.......warranty worthless
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