Oil to use for 1991 petrol tb42 eccs safari

[sprdad]

I am just about to replace all the oils in my Safari and am thinking of using Synthetic or Semi Synthetic in the engine. I have always used Mineral oil in the past however with 300,000 on the clock I thought a change could give better performance.
Would appreciate thoughts and experiences on which is the best option.
Lee

[kevin07]

i use penrite 10-40 semi synth in the crd and shell helix hx7k semi synth in the gq with the recommended dose of lifter free and is wonderful

[billyj]

penrite hpr30, 20w/60 in mine 370k kms turbo tb42

[Clunk]

Castrol magnatec 15w40 in my TB42e, does the job