The Triumph Dolomite Club - Discussion Forum

Hi all,

Curious to know what's the best oil grade or grades for a Sprint engine. When I ran one back in the 90s I always ran it on 15w50. Also, mineral, semi synthetic, or fully synthetic??

Keen to know who runs their engine on what.

Thanks in advance,

Chris.

I will be following this, because I've been wondering the same thing.

i run 20w-50 mineral, have done for 21 years.

Castrol Classis 20W/50.

Paul

Had a good look through the Leyland workshop manual, for the UK it suggests 20w/50 or 15w/50, so I guess the latter a bit thinner in the winter, maintaining the same thickness in summer.

I would think a semi-synthetic 15/40 would be fine. It's never hot enough in the UK to need a 50 weight summer oil.

I had the same thoughts, I contacted Opie Oils a whilr ago and was recommended 15w-50.
I went for Fuchs Pro R Fully synthetic. It may well be over kill in an older engine but it seems to work well and doesn't discolour as much over time and use.

I know the factory recommendation is 20w 50 but my view is that as oil technology has moved there may well be better alternatives.

Thats my view anyway, from the research I did it think it's a case of you pays your money you takes your choice.
Obviously there are limits to this; running you engine on gear oil may not be the best choice!

Aleco wrote:I had the same thoughts, I contacted Opie Oils a whilr ago and was recommended 15w-50.
I went for Fuchs Pro R Fully synthetic. It may well be over kill in an older engine but it seems to work well and doesn't discolour as much over time and use.

I know the factory recommendation is 20w 50 but my view is that as oil technology has moved there may well be better alternatives.

Thats my view anyway, from the research I did it think it's a case of you pays your money you takes your choice.
Obviously there are limits to this; running you engine on gear oil may not be the best choice!

I asked a similar question some time back, I knew what grade of oil to use but was it safe to use fully synthetic in a sprint ?, I was advised not to use fully synth because of the detergents in fully synth which would wash all the sludge around the engine from the old mineral oil and possibly block oil ways and lead to engine failure, it was ok to use fully synth in a rebuilt engine though

( original post thread here viewtopic.php?f=5&t=24106 ).

Yep fair call. I forgot to mention that Opie did ask if my engine was recently rebuilt - which mine is.

What do you recommend to for trans?
In my Volvo M41, with J-Type OD, I'm currently running SAE 30weight. And it works better then the modern replacement that is recommended for them. I couldn't hold constant pressure, and was more noisy in the manual part of the box.

Could this be used in the OD on my Dolly.

I like Millers Classic Sport 20w50 which is a modern spec semi synthetic oil and gives good protection.

If you want oil with a good quantity of ZDDP (anti wear stuff) then Valvoline do a good one in a 20W50 called VR-1. Personally I'd be looking for any decently branded 20W50 oil, mineral or synthetic. Some are quite basic in terms of their API specs for example Comma Classic and Castrol XL 20W50 are both an API SE which is an ancient spec. A perfectly good basic oil but nothing hugely special. Millers Oils do some good formulations which are API SJ but have added more ZDDP for better anti wear. The newer API standard does have some benefits in terms of anti sludge too.

I don't know why Opie oils makes some of the recommendations it does, for my Mazda most were wrong.

Oil technology has indeed developed over the last 45 years, but two things have remained constant in that time; the criteria for oil grading and the make up of a Sprint engine. 20w50 was recommended then, so it still should be!

I use Valvoline VR1 20/50 in both our Sprints. I find it excellent and has much improved oil pressure on a hot engine compared with a classic Pentrite 20/50 which I have also tried. We also used to run VR1 in our Formula Ford in a much more stressed race engine, also with good results.

I have a good friend who is expert with Stag V8s having rebuilt numerous engines. He strongly recommends Pentrite HPR 15 which is a Full Synthetic 15W-60. I have no experience of this myself, but guess if its OK for Stag, then cannot see any reason why it would not also suit a Dolomite which is a similar technology engine. I cannot comment on the issues, if any, of using a fully synthetic oil in a 'dirty' engine.

I'm using Miller CSS semi 20W/60 on my 1850.
The Valvoline VR1 sounds good.