Need Advise of Experts on Mileage Issue with Suzuki Margallah

[hassaaniqbal92]

using 10w30 in a khyber or a margalla wouldn't be very wise since these oils are api sn which are not so zddp abundant. I would recommend using caltex 10w40 api SL in these old school flat tappet engines.

@Xulfiqar

[hassaaniqbal92]

I am using 5w-30 in other newer rides. last oil that i put in Margalla in Aug 2021 before engine overhaul was 5w-30 and the situation got quite worst with it.

car was working fine with 5w-50, with 5w-30 it started reducing oil vigorously, started emitting smoke all the time and lost compression so eventually i had to decide for engine overhaul.

i think 5w-50 was masking quite many issues with the engine specially the broken piston. m kind of reluctant to put 5w-30 in G13B engine.

wats your insight on this?

Use caltex 10w40 api SL

[Thinking]

Thanks for your input.

Does that mean that API SN fully synthetic oils are actually less suited to these engines like G13B?

I actually never faced any issues with Micking 10W-40 API SN fully synthetic and Toyota Taglon 5w-50 API SN fully synthetic been using them for ages.

opting for an older grade like API SL will be more suitable? also what is the change interval with non synthetic oils? i used to change non synthetic oils at 1200 KMs change interval previously. have switched to 5k change interval once started using fully synthetic oils.