Monday, Nov 23, 2009 at 13:47
Hi Peter,
If you are buying second hand, motor wise, I would look at series III and above and IMHO, the autos have the edge as they tend to have an easier life due to the torque multiplication of the torque converter. Also, no dual mass flywheel to change at a later stage either.
The Jatco 4 speed box has been around for a long time and is tried and proven. As such, there a a couple of very inexpensive mods for this gearbox to make it a very good performer and provide things like - the ability to lock up the torque converter in any gear and another mod that alters the gearboxes line pressure to shift so towing is much more pleasurable for the driver and the gearbox.
With the lockup torque converter mod. you have the equivalent of up to eight gears to choose from (eg. 1st, 1st lockup, 2nd, 2nd lockup, 3rd, 3rd lockup, O/D, O/D lockup).
The auto box is also set up
well for touring as it makes the motor rev at around 2350rpm @ 110kph in O/D but as most people tow large vans in drive or 4th gear, in that circumstance, the auto will rev a little higher than the manual (200rpms I think).
Something to remember if you choose to buy any turbo diesel, you need to drive them gently until the glow plugs have turned off (if you cannot do this then let the motor idle until the glow plugs have turned off) and you need to let the turbo cool down before turning the motor off (ideally to 200c after turbo temp - another reason to have an EGT gauge installed).
I copied the following from another thread that I responded to a little while ago in the hope that it explains the "features" of these high tech motors and how they can be made reliable with the addition of some gauges and a blowby catch can:
The "blow up" problem that a few members on other forums enjoy blowing out of proportion (pardon the pun) can be typically contributed to a faulty MAF sensor.
This is not a "Nissan" thing, it is the same on all high tech diesels that do not have an EGT sensor feeding information back to the ECU.
Prevention is always better than the cure so by installing EGT and boost gauges, we are able to see if ever the electronics are not working correctly and we are able to catch all problems (except real mechanical ones) before it causes damage to the motor.
The challenge is really to advise all who have these high tech motors to install the two gauges - then keep on enjoying the truck...
Another thing that we should all be weary of is the implementation of EGR on these type of motors. EGR is not bad per say but when mixed with blowby oil, the exhaust particles turn into goop and slowly block the intake manifold which is very bad for a diesel.
There is a simple fix for this as
well, install a good quality blowby catch can. If you have had your vehicle for a while, then I would suggest that a clean of the intake manifold would also be required (throttle body and inlet of the intake manifold can be accessed and cleaned without too much difficulty).
The 3ltr motor is a good design and members from another
forum that have striped them down after 260Ks have found the internals to have minimal wear, the problem was a hole in the piston due to a failed MAF sensor:
"Just my thoughts from what I found when I pulled
mine down after the problem
at 263,000K
wear in
bore - too small to measure
twist in head - less than 1/2 thou
intake and exhaust manifolds also less than 1/2 thou twist.
big ends - not run in yet. Numbers still readable on shells.
mains - identical with the new ones, thickness, ovality and yaw. no wear there at all.
So with new engine australia pistons, and a weather eye being kept on the maf (with a spare in the glove box) I reckon she's good for at least 1,000,000 K "
As you can see, the motor is good but the electronics are what can let it down - by installing a boost and EGT gauge, it won't get the chance.
Cheers,
Whitie
AnswerID:
392329