View Full Version : Weighing in the options GU 2001
DickieO
6th October 2024, 11:50 AM
Hi All,
2001 GU series 2 ZD30 owner.
ZD is running well (450,XXX km, rebuilt at 200,XXX km) but mental preparation for a conversion if/when the ZD gives out.
Looking at engine options and opinions e.g TD4.2, 4jj1 etc
After the best all rounder with good fuel economy on highways, reliable servicing, and being able to hit the tracks for some fun 4WD.
Diesel - petrol engines not an option.
Manual - definitely prefered
Duramax and 6bt I don't think are really viable options because of the weight of em (correct me if I'm wrong)
My list so far in order goes
4.5L Cummins - good cubes, reliable, overseas parts
TD42 - easy peezy, parts readily available, but they overheat and crank issues.
4jj1 - reliable, powerful but still 3L
M57 - still a 3L, but parts available, timing chain issues?
OM606 - noisy, powerful but overseas part.
I'd be interested to know other experiences, recommendations or other options available.
mudnut
6th October 2024, 09:18 PM
Welcome to the forum.
If I had no option but to to an engine swap, my choice would be the TD42. Easiest to do and the engine is reliable and there are minimal issues with certification for registration and insurance.
As, for overheating, there are a few threads on this forum dealing with things such as radiators, air flow, cap ratings, thermostats, fans and improved water pumps.
An old thread outlining some work to be done. https://www.nissanpatrol.com.au/forums/showthread.php?8253-ZD30-to-TD42-conversion
DickieO
7th October 2024, 01:57 AM
The TD42 definitely has its place high on the list, the heating is my main concern cause I drive from Bris to Sydney and back a few times a year and also up Perisher so those long hill climbs can be challenging.
Thanks for the thread, I'll definitely go through it all.
mudski
7th October 2024, 01:32 PM
I converted my GUII from the ZD to a TD. If I had my time again, I'd would have gone either LS3 or a 6, or a 4BT Cummins. Speaking with multiple Cummins owners now, I do know the Cummins engine make the vehicle front end heavy and it does unbalance the GU's a bit. But having lots of power on tap makes one forget about the little unbalance.
Why would i have gone for a V8 or Cummins? Power, and lots of it. No other reason.
One thing to remember is engineering. Not sure about where you are from but here in Vic, its important to have the certificate, and from a VASS approved engineer also, so the coppers cannot argue against a VASS approved certificate. A non VASS approved certificate can be argued in court if the situation gets to this.
As for the TD's getting hot. Depends on what you do to the engine, and it depends on what you call getting hot. My TD runs a 12mm pump, hi crack pressure injectors, 3071 Garret turbo, Cross Country Ultimate top mount intercooler, and the coolant temps will sit on around 95'c at 100K's on the highway with ambient temps up to around 30c, anything above its around 105c. Which is still under Nissan's boiling spec of 117c. Another thing to remember, the engine block in cast iron. Once they warm up and get hot, they stay hot.
100c temp reading is not hot, its under pressure remember, and pressurizing coolant raises the boiling point. So 100c is technically not 100c it less, by how much? I don't know but there is a way to calculate this which i don't know how.
I also run a water rail which is plumbed into the water jackets of the cylinder head and is connected to the thermostat housing to help draw out the hot coolant in the cylinder head, plus the larger viscous hub and fan and the JPC Hiflow water pump. The radiator is genuine as i found this one to work the best over a triple core copper and triple alloy radiator.
There is no air gaps between the radiator and support panel, and no gaps between the a/c condensor and radiator. AND I even have the plastic air dam under the radiator which is supposed to assist in air flow.
So i've pretty much done everything possible.
So its nothing to worry about in my opinion. I used to constantly worry about it but not anymore. I still do watch the temp gauge like a hawk though.
My last comment to add is, air flow. These TD's do like air flow. The more you have in front of the radiator the less air the radiator is going to get. My last beach trip i remember the old TD quite hot at low speeds, over 110c, so i just popped the bonnet release so there was that little bit more air getting in and this made a BIG difference, which makes me think air flow is the real issue here.
My 2Cents...
Cheers.
DickieO
8th October 2024, 01:31 PM
Appreciated the time and detail you put in Mudski,
Yes definitely will be in contact with an engineer before I start any conversion other than a TD42
I will keep an eye out for a TD wagon, might be more convenient to buy a running wagon, transfer some fruit and sell the zd rig than a conversion. An option i'm fine with.
Good to know that the heating can be controlled, seems like a bit of work went into keeping temps down. Hopefully QLD hotter weather it still capable of keeping it cool.
My last comment to add is, air flow. These TD's do like air flow. The more you have in front of the radiator the less air the radiator is going to get. My last beach trip i remember the old TD quite hot at low speeds, over 110c, so i just popped the bonnet release so there was that little bit more air getting in and this made a BIG difference, which makes me think air flow is the real issue here.
Cheers.
Thats a useful tip to remember, do you run the same zd30 scoop, larger scoop, or no scoop?
mudski
8th October 2024, 04:30 PM
Appreciated the time and detail you put in Mudski,
Yes definitely will be in contact with an engineer before I start any conversion other than a TD42
I will keep an eye out for a TD wagon, might be more convenient to buy a running wagon, transfer some fruit and sell the zd rig than a conversion. An option i'm fine with.
Good to know that the heating can be controlled, seems like a bit of work went into keeping temps down. Hopefully QLD hotter weather it still capable of keeping it cool.
Thats a useful tip to remember, do you run the same zd30 scoop, larger scoop, or no scoop?
Fairline Fibreglass scoop mate. Its made to accommodate the huge Cross country intercooler.
Doing the conversion from ZD to TD is pretty simple. The only cutting and welding needed is the engine mount brackets on the chassis. Plus, you MUST use a TD cross member. The ZD one pulls the TD back about 10mm, its fine in forward, but in reverse the exhaust manifold hits the firewall. I learnt the hard way and listened to others saying they are the same. They are clearly not.
Plasnart
8th October 2024, 05:13 PM
Can I just put my 2c in here. If you decide to go with the TD42, why would you opt to convert rather than just find a good 4.2 rig and buy it? It will be cheaper, quicker, less risk, no work involved, no engineering and you’re driving around the next day. KISS philosophy is always a winner.
DickieO
8th October 2024, 06:04 PM
Can I just put my 2c in here. If you decide to go with the TD42, why would you opt to convert rather than just find a good 4.2 rig and buy it? It will be cheaper, quicker, less risk, no work involved, no engineering and you’re driving around the next day. KISS philosophy is always a winner.
This is my thought process aswell, that way Id be able to do some checks with the engine running and driving, Id have concerns buying a effed TD that's been pulled out and sold.
Doing the conversion from ZD to TD is pretty simple.
My concern is more engine related. Besides oil leaks, turning it over, and external obvious issues. id personally struggle to tell the condition of a motor that's not running, Though a rebuild before fitting would be a good idea either way especially now cause i got time. Would be keen to learn more how to check as much as i can before purchase.
mudnut
8th October 2024, 07:07 PM
Another option if your current Patrol is in really good nick, is places like Readies near Bendigo that specialise in TD42 conversions.
Plasnart
8th October 2024, 07:17 PM
This is my thought process aswell, Id be able to can do some checks with the engine running and driving, Id have concerns buying a effed TD that's been pulled and sold.
My concern is more engine related. Besides oil leaks, turning it over, and external obvious issues. id personally struggle to tell the condition of a motor that's not running, Though a rebuild before fitting would be a good idea either way especially now cause i got time. Would be keen to learn more how to check as much as i can before purchase.
I’m struggling to understand what you’re saying here, but I personally would never buy a motor that’s been pulled from a vehicle. There are even instances of people buying crate 4.2s that are not “reconditioned”. The 4.2 has been used in many vehicles ranging from forklifts to light buses overseas. Be bloody careful.
If you decide on a TD42 just buy a factory TD42 vehicle that has been looked after and not modified. Take your time. Play the long game. Every one you look at you get a keener eye and understand more. Look at lots. Don’t buy the first one. You will find a beauty.
Plasnart
8th October 2024, 07:29 PM
Oh by the way, I don’t know where you are or the type of driving you do, but if you want something fun on the beach or in the dunes, absolutely do not look at a TD42. If you want wheel spinning horsepower this is not your donk. But if you want low down grunt, a torque monster that can walk technical tracks, that can grind its way up steep inclines without having to rev the shit out of it and suspension bounce your way uphill out of control, then this is the motor for you.
DickieO
9th October 2024, 01:57 AM
I'm located in QLD, so beach driving is mostly what ive done so far. Morten Island, Fraser Island and Bribie Island.
But future places I want to visit include the tracks upto cape and through the Simpson desert, I just don't have as much confidence taking the ZD30 on either of them
So yeah trying to figure out which engine is the best for me. I've seen the TD42 do plenty and think it's a good option.
Wheel spinning power does sound appealing i wont lie. Can a 6bt or a duramax get as much enjoyment on say the old telegraph track?
Plasnart
9th October 2024, 08:38 AM
I don’t know anything about your other considerations so can’t comment. The TD42 will be great for the cape and simmo, just not as a dune buggy. I took mine outback and through dune country similar to the simmo multiple times and it was fantastic. I had it on beaches down in SA and it was fine, but it was not suited to climbing through the dunes at Fowlers Bay.
pollenface
9th October 2024, 09:45 AM
EV conversion with a range extender motor
DickieO
9th October 2024, 12:58 PM
I don’t know anything about your other considerations so can’t comment. The TD42 will be great for the cape and simmo, just not as a dune buggy. I took mine outback and through dune country similar to the simmo multiple times and it was fantastic. I had it on beaches down in SA and it was fine, but it was not suited to climbing through the dunes at Fowlers Bay.
Really appreciate all the help and info. Td42 is solid option at the moment.
EV conversion with a range extender motor
An EV project is definitely not on the cards, a di pietro engine conversion would be awesome to do and I'd be interested in 🤑
pollenface
9th October 2024, 04:55 PM
An EV project is definitely not on the cards
haha, I didn't think so
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