Can a missing oil dipstick tube o-ring cause a drop in oil pressure? 1995 dodge van with a v6. I am new here and hope I am posting correctly

 

Instantly, no, over time, when driven in dusty dirty conditions, then yes it is possible.

Do not trust the stock OP gauge.

Check hot oil pressure with a real gauge, or install a real electrical or mechanical gauge. The dash gauge is not accurate or precise, and is little better than the idiot light, in my experience with both a mechanical gauge and the stock gauge operating simultaneously.

 

Allow me to explain. I had a lot of lifter noise and a steady 40 lds oil pressure. A mechanic convinced me I needed new lifters. I paid 600 to have it done. Now, My oil pressure when cold is about 60 lbs, but drops to 20 when engine is warmed up and idleing. Then Back to 40 when cruising. Still have the lifter noise, but only after engine is warmed up. I noticed my dipstick tube is real loose and do not remember it being loose before the work was done.

 

It's not the lifters, it's more likely a rod bearing.

You need the dipstick o-ring to seal the crankcase for the benefit of the PCV system.

 

Thanks for the quick reply. I am in agreement with you about the rod bearings. I just chose the wrong mechanic to do the work

 

The oil pressures you list are expected, and ticking lifters are hardly an engine eater anyway, more an annoyance, or in this case, a contribution to the college fund of the mechanic's daughter.

 

 

A new timing chain can begin to get noisy after only a short time. If your engine doesn't already have it this guide plate is a nice addition when replacing your chain and gear set.

http://shop.advanceautoparts.com/web...ntent=10711125