Hi,I 've got a 88 Cherokee 2.5L four banger with 235,000 mile on it,she has a little blow by and I've been using high mileage 10w40 but I was reading in the tech forum about it recommending Rotella for the 4.0's,but hardly no info about the little 4 banger,the question I'd like to ask is this,can I use Rotella in the 2.5L and what weight ,the 15w40 or the 5w40,the biggest reason is the low oil pressure,at idle I might see 5 to 10 lbs if the old stock gauge is right,so any suggestions would be appreciated. thanks in advance"

 

Run the recommended factory weight. Check oil pressure with a mechanical gauge. Do not rely on the gauge in the cluster.

 

Rotella T4 15-40 with a Wix filter.