Hello all, I am experiencing power loss after 55km PMS.
I am aware that certain dealers use certain oils however, it should give the same performance or at least, no power loss at all.
It's a Gen2 Montero Sport GLS Premium and the problem is, on 1st to 3rd gear, everything seems to be fine.
At 4th above, engine sound is noticed and it's like dying. Can hardly even hit 160kph.
Checked the air filter. It's new and seated properly except that, 1 hook in front that holds the cover is broken.

Unsure really what happened.
Hope you can help me. Thanks.