Oil recomendation

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Just to answer a question I missed...why go up a viscosity grade at the hot end. Simply because my experience of using aftermarket rockers and shafts suggests that this is the place that oil pressure bleeds from. Using brand new steel rockers and a new shaft the oil pressure light would come on when hot. I immediately swapped back to old land Rover parts. No light. Quality rockers and shaft are very expensive (£800+) from land Rover so my guess is most v8 s are on original or new but crap shafts/rockers leading to lower than ideal oil pressures.
 
That's really quite curious. I would be amazed that a fairly small rocker shaft could loose so much oil to drop the pressure off - I would have thought it would be so noisy from wear or just excessive clearances that it would be untenable long before pressure issues became apparent.
 
Every v8 has an engine oil cooler but still runs hot! 20/50 after 6mths of towing will be to thin when hot.by all means run 20/50 full synthetic .

Our D2 V8 had an oil cooler for the engine and one for the gearbox.

We ditched the engine oil cooler and run 10W-40 or 15W-40 Diesel oil in them all, three V8's and a Rangie.

Peter
 
It's true replacement steel rockers are badly made the only reason they make them in steel is because the replacement Ally rockers are so poorly made the pads fall off. The shafts are undersize to. It doesn't take much gap to have catastrophic oil pressure. I've not brought enough varieties to say there all crap though. But land Rover originals are ok but often very badly worn under the shaft.( But still better than replacement)
If any one knows of good(cheap)uns speak out now!
 
I have heard of ditching the engine oil cooler I think it was standard in Scandinavia. But if your towing 1 ton with mineral oil in summer you'd best keep it on. Hotter climes definitely keep. Why did you decide to ditch the oil coolers listerd?
 
Just to answer a question I missed...why go up a viscosity grade at the hot end. Simply because my experience of using aftermarket rockers and shafts suggests that this is the place that oil pressure bleeds from. Using brand new steel rockers and a new shaft the oil pressure light would come on when hot. I immediately swapped back to old land Rover parts. No light. Quality rockers and shaft are very expensive (£800+) from land Rover so my guess is most v8 s are on original or new but crap shafts/rockers leading to lower than ideal oil pressures.

Ask Mozz Smith!
 
I have heard of ditching the engine oil cooler I think it was standard in Scandinavia. But if your towing 1 ton with mineral oil in summer you'd best keep it on. Hotter climes definitely keep. Why did you decide to ditch the oil coolers listerd?

Not really needed, we do tow a lot as regulars will know, but out of the two coolers, we felt that the gearbox cooler (R380) was more important, especially as the engine cooling system was functioning OK. We took the rig to the South of France in 35 Dec C temperatures and it was fine, temperature never moved from the middle of the gauge.

Having two coolers in front of the main radiator isn't good either.

Peter
 
I bet a mineral would struggle with 10000. And the engine would be scrap after 100000.

You could well be right with the first part but I disagree with the second statement - I had a 3.5 RRC, which I sold 9 years ago, that ran well & still had factory spec. compressions at 160K. I obviously didn't know it's service history, but what from what I heard about the PO I doubt he paid out for expensive oil lol. During my ownership it ran on 20/50 mineral changed annually / around 3K.
 
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I use full synthetic in the Jag but I'd never risk leaving it 30k miles. 10k, yes.

Modern oils though are very good - unless you do testing you have no idea. The LL04 I am using for the BMW is within spec still for all markers at 30k, it's getting a bit low on TBN which is what the condition sensor looks at in the oil to decide when to change it - but there is no loss of viscosity, shear stability, etc...
 
You could well be right with the first part but I disagree with the second statement - I had a 3.5 RRC, which I sold 9 years ago, that ran well & still had factory spec. compressions at 160K. I obviously didn't know it's service history, but what from what I heard about the owner I doubt he paid out for expensive oil lol. During my ownership it ran on 20/50 mineral changed annually / around 3K.

My disco with 3.9 V8 was on 110,000 miles when I sold it. It is still running like a clock, and never seen anything but mineral multigrade oil in it's life.

I agree with Lister, transmission oil cooling is more important than engine oil cooling.

And not sure why anyone would feel towing a tonne was a big load on their motor. I have rarely towed less than 3 tonnes with a Landrover, and not had any reliability issues.
 
Modern oils though are very good - unless you do testing you have no idea. The LL04 I am using for the BMW is within spec still for all markers at 30k, it's getting a bit low on TBN which is what the condition sensor looks at in the oil to decide when to change it - but there is no loss of viscosity, shear stability, etc...

Modern synthetic oils are excellent, so good that it is hard to run an engine in with them. I use synth in the Mondeo, which probably has the same engine as in your Jag.

But those engines are designed for synthetic oils. The Rover V8 was designed for mineral oil, synthetics did not even exist at that time.
 
Modern synthetic oils are excellent, so good that it is hard to run an engine in with them. I use synth in the Mondeo, which probably has the same engine as in your Jag.

But those engines are designed for synthetic oils. The Rover V8 was designed for mineral oil, synthetics did not even exist at that time.
I don't have a Jag... that's someone else.

As for "designed" for mineral or synthetic - that's a total red herring. Engines are designed for certain tolerances and then an oil which will maintain appropriate flow rates, film stability and shear, shock loading and contact scuff etc is chosen. That can be fulfilled by synthetic or mineral base stocks - the engine wont care.
 
I don't have a Jag... that's someone else.

As for "designed" for mineral or synthetic - that's a total red herring. Engines are designed for certain tolerances and then an oil which will maintain appropriate flow rates, film stability and shear, shock loading and contact scuff etc is chosen. That can be fulfilled by synthetic or mineral base stocks - the engine wont care.

Apologies, it is Grrr has the Jag.

Dont agree about the design. Modern synth oils are far too thin for older engines, and so slippery they can lead to glazing of the bores.
Newer engines like synthetic oils, and run more economically and have smaller oil capacities as a result of using such oils.
 
Synthetic oils can be any viscosity you like. Classic oils also sell a 20/50 mineral and a 10/40 mineral there own brand with 1200ppm zinc. It's £17 /5l. They sell about 5 different 20/50 minerals. Including golden film and Piston eze.
 
My old V8s 3.5rrc 3.9rrc ran on 20w50 never had an issue, and they ran like swiss watches.

my other engines 2.25 and 2.6 engines ran on SAE 50 without issue

The current tow pig 4.6 rr p38 runs on shell 10w40, changed every 5k.
my old vm ran on anything i had lying around in my shed usually a mix of 10w40 and SAE 60 lol
i've always change my oils regularly every 5k max and my engines have never let me down.
 
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Technically the rv8 was designed(at least the oil pump and bearing and tolerances) in1995 with 5/40 being the universal approved oil. I assume lr designed the pump to run on it's approved oil. What was the last lr to give 20/50 as its recommended oil?
 
Technically the rv8 was designed(at least the oil pump and bearing and tolerances) in1995 with 5/40 being the universal approved oil. I assume lr designed the pump to run on it's approved oil. What was the last lr to give 20/50 as its recommended oil?

You quote the rv8, do you mean the short run MG rv8?

Cheers
 
No I mean Rover v8 specifically serpentine engines with crank driven oil pumps. Mgrv8 s had Rover v8 though an intermediate front cover I think. In fact 10/40 was the recommended oil for those. And these had a cam driven pump.
 
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