LOW Oil pressure

[MudSurfer]

After a successful transfusion yesterday, new 5W/30, Slick50 and MolySlip and filter - the truck is much quieter however, on driving to work this morning the oil pressure was consistently in the lower end of the 'large block' on the dial. When I was stopped, it dropped to the middle of the last block on the left of the dial.

What would cause this, and am I safe to drive home (30 miles)???

TIA

[dirtydog]

mine runs just shy of the first line on tickover but I use 10w40.

talking of which I did a "Tony" on Sat. I didnt do my new oil filter up on properly and after filling I ran the engine then checked the dipstick which showed nothing!
I looked under the truck and it had proceeded to junk all the oil straight out of the filter all over the floor!
It still looked black though so it probably did some good having a bit of a flush out, just as well I had a new barrel of oil waiting

[TonyN]

[MudSurfer]

This is the lowest I have ever seen the pressure - and am concerned that it is so low after an oil change too.

I'm not going to be able to view this forum much (if at all) during today as my office network will block it - if you have answers, can I be cheeky and ask you send them to itbloke@tiscali.co.uk

Many thanks!

[TonyN]

You're oil is probably slipperier with the additives, so the pressure is less. Molyslip AND Slick50? probably a bit over kill......

[MudSurfer]

Hi Tony

Thanks for sending that - excellent..

It does look as though its OK, at idle it is in the lowest area indicated above, as with driving, at the lowest point. It may be that I just need to top up now that I've driven more than 2 miles (which is what I did when I finished the change) - so I'll check and top up tonight before I go home and see how it looks. Is it feasible that the level will have dropped after a good run up the M40?

[MudSurfer]

You're oil is probably slipperier with the additives, so the pressure is less. Molyslip AND Slick50? probably a bit over kill......

It was making a lot of noise

[Gamedawn]

Also isn't 5W/30 a bit thin?

[MudSurfer]

Also isn't 5W/30 a bit thin?

I've gone for that as it's fully synthetic and should last a bit longer - but I guess it does explain the lower pressure.

[huff_diggler]

mine runs just shy of the first line on tickover but I use 10w40.

talking of which I did a "Tony" on Sat. I didnt do my new oil filter up on properly and after filling I ran the engine then checked the dipstick which showed nothing!
I looked under the truck and it had proceeded to junk all the oil straight out of the filter all over the floor!
It still looked black though so it probably did some good having a bit of a flush out, just as well I had a new barrel of oil waiting

so you have no probs with 10w40 then? thats good i have about 20l's in the garage.

[The Hornet]

I used that Molyslip and noticed mine had dropped as well. I wouldn't use it again and have stopped using that engine flush as I can see problems developing if I continue to do so. Sealing deposits being removed and oil pressure dropping etc.

I use Carlube 15w40 TD oil and change every 5K. This is full fat oil, not any synthetic added.

[MattF]

You're worrying over nothing. What you describe is perfectly normal for most of us. 5W/30 does seem a tad of an unusual choice, however. Also, if you have used fully synth, the additives are a bad idea. The whole point of full synth is that it contains no impurities of its own, which is why it doesn't gunge up like other oils. The additives are reintroducing those impurities.

[TonyN]

I've gone for that as it's fully synthetic and should last a bit longer - but I guess it does explain the lower pressure.

To be honest, its a deisel motor designed in the early 90's, fully syn is probably on the thinner side of what its designed to use, plus as has been mentioned, removing deposts on an old happily running engine is normally a bad idea, as you often end up with oil leaks, higher oil consumption, lower pressure, noises, etc....

I always just use a good mineral oil, or semi syn if you want and change it regularly.

[dirtydog]

so you have no probs with 10w40 then? thats good i have about 20l's in the garage.

not for the last 2 years, change it every 5000kms.

[MudSurfer]

To be honest, its a deisel motor designed in the early 90's, fully syn is probably on the thinner side of what its designed to use, plus as has been mentioned, removing deposts on an old happily running engine is normally a bad idea, as you often end up with oil leaks, higher oil consumption, lower pressure, noises, etc....

I always just use a good mineral oil, or semi syn if you want and change it regularly.

So - is it worth me using this for a short while and changing to 15W/40 or just dump it this weekend and get full mineral oil in asap and stop bothering everyone with my dumbness??