How to drive the RD28T

[Crimpy]

It may seem like an obvious question but this is my first time owning a diesel (GU rd28td) and I wanted some input on how people drive theirs in terms of rev ranges and whether anyones fitted an ultragauge or similar product to test consumption across rev range?
The rd28td seems to go goes against what I'd heard most diesels have a strength in, being low down torque, as it feels tremendously weak before 2000rpm lol
Couldn't find much with a search but I'm hoping there's some proud 2.8 drivers willing to share their driving habits.

[PeeBee]

Crispy, I bought a new gq td2.8t in 1997 and have just swapped the engine out. I can offer my thoughts after looking after one since then. They are a horribly torque-less engine until you get them to 3000rpm then they have a moderate chance of holding speed on a hill. Mine was so poor I ended up putting a marks 85% reduction gear for low range and it transformed it off-road. Biggest thing was getting a k&n air filter and keeping it clean as engine will bog down if restricted. I also fitted a snorkel and safari inter cooler and picked up some gains there. Keep on top of fuel filters and oil changes. Keep the overall weight of the vehicle down as the fuel consumption will rise badly. When the ambient temps rise over say 35 degC lower your speed on the open road and watch the temp gauge as these motors are renowned for overheating, but saying that I only ever had 1 day that left me feeling like the engine was running on 3 cylinders and that was my own stupidity for pushing too hard in 44 deg C. Mine was a solid engine with only 120,000 on it and it was very reliable and trouble free. I changed the engine because I wanted more hp and torque, plus will be looking to tow a camper and I didn't think the 2.8 was what I really needed. Hope this helps.
PHIL

[Crimpy]

Thanks Phil this is the kind of stuff I was hoping to hear about. In your daily driving did you regularly rev over 3000rpm? I know where the red is on the tacho but I haven't been game to take it right out there yet haha.
Where has your 2.8 ended up if you don't mind me asking? Thanks for the heads up re. over heating too.

[PeeBee]

Crimpy, yes regularly up near the start of the red line, more in first or second then eased off. The revs rise of course also for 4th to 3rd drop downs. The engine does like to rev and is comfortable doing that. I did an engine upgrade to a Brunswick Diesel 6.5 V8 Optimiser crate motor - non turbo. I am waiting for it to leave Perth now. I traded my engine in with them and got 4K for it. It was in perfect condition and well maintained. I could only really limp it around if it was totally empty and when full needed a fair share of clutch slip to get it of the mark. The motor will start retarding when the revs get too high, and I think a lot of young guys give these motors a flogging and get a shorter life accordingly.

[Crimpy]

Mate that is quite an upgrade in capacity! Ah good stuff. Did you fit any gauges to your previous setup Phil? And you never had any problem with the k and n filter or keeping it isolated from external environment?

[PeeBee]

Mate that is quite an upgrade in capacity! Ah good stuff. Did you fit any gauges to your previous setup Phil? And you never had any problem with the k and n filter or keeping it isolated from external environment?

I fitted a boost gauge off the inlet manifold, an EGT off the exhaust post turbo, ran two aux temperature probes off the radiator to get a real understanding of the coolant temps, digital volt meters on main and aux batteries, but all this gear was dash located, not in a pillar pod. The pods look good but I wonder what sort of distraction or annoyance they might become with the glow right at your eye level?
I had an exhaust upgrade in the pipeline before biting the bullet on the new engine. I see a number of guys upgrade in the area of 2.5 - 3" with good results.
The K&N was located inside the safari Snorkle airbox - the 2.8 snorkle comes with its own plastic airbox fitted on passenger side. The thing to watch is the air inlet from the snorkle is on the side of the filter housing, and tends to build up locally with all the bugs, dirt leaves etc that fly down the snorkle. The local impact zone can clog up quickly, however the weave of the K&N still gives great efficiency, to a point - again its another maintenance focus point. The filter was purchased off ebay - around $120 from memory - then you have the service kit at circa $35?. I believe they are worthwhile for sure, as a factory element is around the $35 mark and if you are doing big klm's you will chew thru them. Also the factory ones dont breath well when they get moist and the dirt turns to a fine mud - the K&N must lose efficiency also under these conditions but didn't seem as severe.

[Crimpy]

Champion, that's some top notch info thanks mate. It came with a snorkel fitted so appreciate all the knowledge!

[Crimpy]

Crispy, I bought a new gq td2.8t in 1997 and have just swapped the engine out. I can offer my thoughts after looking after one since then. They are a horribly torque-less engine until you get them to 3000rpm then they have a moderate chance of holding speed on a hill. Mine was so poor I ended up putting a marks 85% reduction gear for low range and it transformed it off-road. Biggest thing was getting a k&n air filter and keeping it clean as engine will bog down if restricted. I also fitted a snorkel and safari inter cooler and picked up some gains there. Keep on top of fuel filters and oil changes. Keep the overall weight of the vehicle down as the fuel consumption will rise badly. When the ambient temps rise over say 35 degC lower your speed on the open road and watch the temp gauge as these motors are renowned for overheating, but saying that I only ever had 1 day that left me feeling like the engine was running on 3 cylinders and that was my own stupidity for pushing too hard in 44 deg C. Mine was a solid engine with only 120,000 on it and it was very reliable and trouble free. I changed the engine because I wanted more hp and torque, plus will be looking to tow a camper and I didn't think the 2.8 was what I really needed. Hope this helps.
PHIL

Were you happy with the 85% reduction gears, what made you go 85%?

[gbab01]

Hi Crimpy.

I had a 2.8TD GU for about 5 years now. They are a quirky motor no doubt about that but once you work them out I think they are good motor. Yes, they are poor down low for torque. You will need to ride the clutch on a slope to get going. They can take a bit of forethought as you drive in to a sloping intersection etc. Revving over 3000 is no problem and you should find that third hear pulls all day. I have towed with mine, a small van. Don't tow in 5th that's a recipe for disaster I am told. Fuel consumption could be better but think about what it's pulling around. On the up side I have found that consumption of fuel towing is not much different than general use around the city so it's fairly predictable. I have a boost gauge and a EGT which I have found worthwhile as the can get warm going up hill. Off road in low range I have found it to be excellent. It will get you where you want to go. I recently had to replace my MAF sensor as I found the power was really down. It made a huge difference (recon unit eBay $100). There is plenty of info around on how to check they are working properly. The one thing I would really push home to you is to get the oil and oil filter changed every 5000 k's. Overall once you have worked it out I think you will find it serves you well.

[Crimpy]

Thanks mate both the boost and EGT are on the list; don't seem too expensive and both worth while. Where abouts did you install yours?
Have you got the standard exhaust on yours? Curious to know how that impacted temps if you have upgraded to 2.5 or 3 inch.

[PeeBee]

Were you happy with the 85% reduction gears, what made you go 85%?

Crimpy, I am very happy with the 85% reduction gears, in fact had the transfer case swapped over to the Chev conversion. I went this way for a couple of reasons and there are some negatives as well that have eventuated over time.

My vehicle was very heavy from carrying far too much crap, and the little 6 cyl just didn't have the engine braking in low range I wanted. Additionally I found I had to hit the harder/trickier stuff uphill harder as well and just am allergic to unnecessary damage. The 85% gears slow things down nicely and feel like perhaps 1.5 gears below first low before the swap. I have used them on many occassions when traction was limited and a really 'soft approach' was required instead of redlining through the obstacle.

The negatives are that the gears are very noisy compared to the original factory gears. They howl and have a distinctly coarse sound. Top speed in fifth on the redline is circa 30kmhr, and the 2.8 is hopeless in high range, so for Vic Alpine stuff its great. For sand its a pain as you need to be playing in 3 or 4th low and driving is on the knife edge. i could never do a Simpson desert crossing with the low range gear set, and with the torque-less engine in high range would stutter at the first sand dune out of Dalhousie - and yes i have done the crossing west to east In some regards I lost a lot of flexibility going so low, but as i spend most of my free adventure time in Vic high country the gear set worked beautifully for me. Also came in very handy a few times when vehicles had to be recovered and towed out of the bush over extended distances - the likes of the back of Wonnangatta to Melb and Butcher Country/Caledonia river valley via Dingo hill before it was converted to switch backs etc.

Looking forward it will be interesting to see if the new set-up is over geared for what i actually need. i have done the comparison and the low range/1st comes up from 70:1 to circa 60:1, however I am yet to feel the braking effect of the V8 diesel, so time will tell. I think there is a fair amount of support for the 60%? gears as a good compromise if your motor can develop torque above that of a mosquito! Bit long winded, but the complete picture from my end.

[Crimpy]

Handy to know mate. I think I'll lean away from that much reduction as we're setting the patrol up mostly to travel around Aus. Though a serious downside is the fact that the eastern side of melb where we are can have some fairly serious hills.
Have you had the v8 on the dyno?

[PeeBee]

Handy to know mate. I think I'll lean away from that much reduction as we're setting the patrol up mostly to travel around Aus. Though a serious downside is the fact that the eastern side of melb where we are can have some fairly serious hills.
Have you had the v8 on the dyno?

No not yet on dyno, still waiting to get it back. Its a brand new motor so will wait until it loosens up a bit.

[gbab01]

Thanks mate both the boost and EGT are on the list; don't seem too expensive and both worth while. Where abouts did you install yours?
Have you got the standard exhaust on yours? Curious to know how that impacted temps if you have upgraded to 2.5 or 3 inch.

Hi. Just got them in a dual pod holder sitting on the dash. May do the pillar pod thing in the future. There is an access grommet down in the drivers side footwell which should enable you to run all the wires and tube without drilling through the firewall. I also ran the wires and tube to the turbo gauge in the gap between the windscreen and the dash - no holes in dash. If and when I change to the pillar pod they will simply run up in to that location as well. Have not changed the exhaust but I probably will at some stage int he future - not sure if 2.5 or 3 as I haven't really looked in to it at this time.