'97 Buick LeSabre

[jvpwdc]

'97 Buick LeSabre, V6 3.8 liter engine was fluctuating between 55 and 70 psi oil pressure @ 70 - 75 mph highway speed. Is this o.k.? If not, what could be wrong ??

[GTP Dad]

Yes it is OK! You are probably seeing fluxuation due to oil drain back. At those speeds the engine pumps a lot of oil and it takes a little while to drain back to the pan. 55 psi is fine and the fluxuation is normal.

[maxwedge]

This can also be caused by too much oil, causing aeration and consequent pressure fluxuations, a bad sending unit has also been known to cause this Ordinarily the oil pickup is constantly submerged, so these other issues should also be looked at.