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Discussion Starter · #1 ·
hello GT people

im was wondering if my 5w-40 Castrol GTX Magnatec oil will "work" whit my orginal. 1,9s engine

and if people could wright their engine oil here that could be a nice way to tjek out whit oil is the bedst ect.
 

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CodeMasteR said:
hello GT people

im was wondering if my 5w-40 Castrol GTX Magnatec oil will "work" whit my orginal. 1,9s engine

and if people could wright their engine oil here that could be a nice way to tjek out whit oil is the bedst ect.
We do not have this oil here in the US, so we can't compare it. I think you will find that a lot of US oils are very different from other parts of the world because of different driving styles and roads.

Bob
 

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Engine Oil

The Castrol 5W-40 will work. However the newer oils that are full synthetic will leak a bit with the oil gaskets. The oil pressure will be slightly lower possibly with the multiple viscosity oil. A blended oil or convetional oil will probably not leak and maintain a bit higher oil pressure.

Good luck.
 

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Discussion Starter · #5 · (Edited)
RallyBob said:
We do not have this oil here in the US, so we can't compare it. I think you will find that a lot of US oils are very different from other parts of the world because of different driving styles and roads.

Bob
okey this it true bob but maby people from the USA may also whant to have this tread to see what kind og oil people have in the engiens... and if their have had a god experience yousing it...

sry for my bad english grammar :) why do i speak danish :confused:
 

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Discussion Starter · #6 ·
David McCollam said:
The Castrol 5W-40 will work. However the newer oils that are full synthetic will leak a bit with the oil gaskets. The oil pressure will be slightly lower possibly with the multiple viscosity oil. A blended oil or convetional oil will probably not leak and maintain a bit higher oil pressure.

Good luck.
hmm okey this is a fully synthetic oil... on a scale from 1-10 (10 is bedst) how bad is the loss in oil pressure ?
 

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My Gt with a 1.9 running on Mobil 1 synthetic has the following pressures

2.6 bars at idle - cold
2.3 bars at idle - Normal operating temperature
3.8 bars at 3000 rpm - cold
3.5 bars at 3000 rpm - Normal operating temperature
 

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castrol

I use castrol high mileage. sae 10-w30.. works ok i guess... if there is anything that works really good let me know...
 

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i seen a 289 small block ford that ran for 14 years on castrol after a fresh rebuild, and it was ugly. oil religousely changed at 2,500 miles, and the engine only seen 22,000 miles, probably the most gunked up motor i've seen torn down. i prefer valvoline of any kind, i run 10W30 MAXlife in my GT.
 

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Yes!

CodeMasteR said:
hello GT people

im was wondering if my 5w-40 Castrol GTX Magnatec oil will "work" whit my orginal. 1,9s engine
We run the Castrol Magnatec in a 2.0 L Isuzu Piazza motor here with 260,000 kms on the clock - no leaks, no problems, good oil.

Also run Duckham's 20W-50 in a Rover all alloy V8 with hydraulic lifters that are getting a bit "tired" - 320,000 kms. The motor sounds as quiet as a new one.

Neither oil will do any damage to the motors as long as oil changes are made regularly (once pre-winter and one pre-Summer) with an oil filter change each time too. Don't go much more than 5,000 kms between oil changes.
 

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I had a 72 GT with around 106xxx on the odometer- no leaks at all, put Mobile One synthetic in it before a thousand mile trip home and it started leaking after that. Bummer, but now I hear thats what happens when you put synthetic oil in when its an older engine, although the PO had said it had some seals replaced not to long before I got it to stop it from leaking. All I know for certain is it was dry when I got it and wet after I put the synthetic in.
 

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A number of years ago I switched to Mobil 1 synthetic in the Turbo GT. This was when the stuff first came out. It didn't take long for it to be leaking front and rear and the turbo seals to let go. I have a synthetic in the tranny and it leaks. I hate the stuff and will never go there again. I've used variations of weights for climates of Castrol for years. I build motors knowing they will be driven hard and Castrol has never let me down. I rebuilt the first 11:1 motor 3 times and it was always clean inside.
 

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I had an experience like that once with a fleet of Mack mixer trucks. They had the Fuller CEMAT transmission, basically a typical truck trans that had a torque converter instead of a clutch and a computer shifted the gears with air operated solenoids. Practically an "automatic transmission." They used regular ATF for oil, but there were overheating problems... A suggested fix was to switch to a Caterpillar synthetic oil which helped the overheating BUT every dang one of 'em practically INSTANTLY started leaking said oil out of the starter seal. The starter tech man said you MUST use a synthetic-compatible seal in the starter.
See why I say "I learn somethin' new every day. Still."
 

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I ran nothing but Castrol 10W-50 oil in my Opels for years with excellent results. For racing engines, I found that Kendall was a bit better in terms of protection and oil pressure.

But in 1992 I started using synthetics. Tried 5W-50 Mobil 1 and hated it. Didn't have any leaks, but my engine's oil temps and water temps were higher (at the track), and hot oil pressure was a lot lower. No damage was done, it protected fine, but I wasn't happy with it. I switched to Redline 10W-40 and loved it. Better pressure, lower temps, and virtually no wear even after 48k of mixed street/racing use (after a teardown inspection). Never leaked from the engine, tranny or diff, but in all fairness the seals were all new when the synthetics were first put in.

Since about 2001 I've used Amsoil synthetics pretty religiously, if only because it's cheaper and more available than the Redline. Still not cheap, but neither is an engine.

Bob
 

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Oil/Gear lube

Because opel trannies seem to be a a bit on the noisy side is there any recommendation on lube to meake them quieter?

I live in Arizona and some one said to switch from 90 weight to 140 for both tranny and rear end
 

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azopelnut said:
Because opel trannies seem to be a a bit on the noisy side is there any recommendation on lube to meake them quieter?

I live in Arizona and some one said to switch from 90 weight to 140 for both tranny and rear end
It would make them quieter. I won't do that anymore here in CT, in the winter I've had my car stall when I let the clutch out in neutral from the extra drag created by 140 wt gear oil! Plus it won't even shift until it has run for at least 3 minutes and warmed up a bit.
 

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Castro 30 Weight

I run 30 weight in my Opel GT and my other 5 cars, mostly Castro, but I will buy just about any major brand that is on sale as long as it is 30 weight.

I have not tried synthetic, and may try it when the GT gets a rebuild. To be honest, I have no condition which requires unusual protection other than high-mileage engines. My most demanding condition is the initial startup of an engine after it has sat idle for a month or so.

My cars are both foreign and domestic, 4 & 6 cylinders, 1972 through 1996. We have 6 cars; all but one has over 100,000 miles. Our climate is very mild, milder than Europe, no snow, no freezing, no hot temperatures. So we do not need the viscosity of a 5 weight. Occasionally we venture into the Great Central Valley of California which has high summer temperatures, but the 30 weight performs well. The most rigorous driving condition we face is stop & go traffic, and of course, starting the engine after a month of sitting idle.
 

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Running a heavier lube in the diff and trans is really not at all where modern technology is at these days, in fact it seems to be the opposite. I have helped my friend a bit with his 28 Model A restoration and we put in the recommended lube. Get this! 600 weight oil! Barely even pours. We warmed it up to about 120 to get it to flow.
Modern big rigs are using a 50 weight synthetic. Less drag, good lubrication, good for high temp. (Guess how hot that big truck trans gets pulling 80,000 pounds up Lookout Pass- try 380 degrees!)
Other than the possible seal compatability issue, THAT is what I'd try in the trans and diff. I trust Bob's thought that NEW seals would handle it ok.
I wish I could run synthetic oils in MY GT. I would do it in a heartbeat. But it's illegal at our racetrack. Apparently when it gets on the asphalt surface they can't soak it up. It's that slippery.
 

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Rover

In the late 1970's Rover (actually British Leyland - the box was used in Jaguars too) has big problems with syncros jamming and not operating at lower temperatures and used Automatic Trans lube in their five-speed manual boxes with complete success. I guess synthetic auto trans fluid would be even better these days. Friction reduction is one of the keys to reducing noise so the addition of some 'Slick 50' or 'Molyslip' would probably be beneficial. A very noisy Triumph motor cycle gearbox was quietened down using the Dextron II/Molyslip mixture. - made it far easier shifting too.
 
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