lubes and cool

[aegir slc]

hi there, looking for the best oils for my '78 350's engine and gearbox, also the best brand and mixture for engine coolant,cheers

 

[Myros]

it all depends on what you've been running

in it until now, and how deep your pocket is.
If you've done many thousands of happy miles on mineral oil, I wouldn't bother changing to synth unless it really gives you a pain. I changed to synth only because our car had had some work done on it and I ran all the others on synth, so it kept things simple for me. The longer change intervals/ability to stay in shape means I'm not paranoid about changing once or twice a year like I would be with mineral oil, and even that isn't necessary given my under 6,000 a year mileage.
The SL engines were designed to run on mineral or semi-synth oil. There isn't much advantage to running on synth except peace of mind. There is some anecdotal evidence that the synth can dislodge dirt and muck and bung your engine up, and find new leaks where none existed before. I can't say that it did on ours, but maybe we were just lucky.
Synth costs 2 or 3 times as much as mineral, and if you don't need to spend that money at 8 litres an oil change, save it and spend it on petrol.
Having said all that, the kind of driving you do is important. If you do a lot of short trips without really warming the car up thoroughly, then lots of oil changes are the ticket for you. I'd be looking to halve the 6,000 interval and go for twice yearly in that situation. and a new filter every time. Mineral oil would probably make more sense economically then.

As for the transmission, just use what MB recommend, which I think is a Dexron II ATF fluid. It does the Power steering too.

Brand names don't count for much, as long as the products meet the relevant specs for the job they are doing. You can't go wrong with Fuchs oil, available from GSF. I use it, and I also use Chevron 5w40 Fully Synth which I get from Costco. I'm happy with Comma ATF in a 5 litre can from the motor factor ( I have 3 trannies and power steerings to look after).
Mobil 1 is good, but pricey. Shell Helix is fine, indeed, you'll find most of the big oil companies make something that you can use quite happily. I use Carlube 5w40 fully synth in the CDI currently, but will probably go to the corresponding Fuchs oil at the next service ( easier for me to get).

Engine coolant , use Bluecol ( Glycol) or any other Glycol coolant. Make sure you use one with corrosion inhibitors. Most of the big names or motor factor variants are fine. Strength varies on the weather where you are, but a 25% coolant to water mix will do for most continental Europe in spring/summer/autumn. If your winters are down below minus 25 Celsius, then you'll be looking to run more like a 40% mix or stronger.

There is a lot written on this site about oil. You could do worse than look up some of the offers from Oilman. Just search the site and see what pops out.

 

[wireman]

Dont go past 50% antifreeze, the cooling properties are markedly reduced at high concentrations,.

 

[aegir slc]

wow! thanks very much for the super in-depth advice,much more detailed than i expected and hugely useful,thanks again