Maybe the mating surface of the heat exchanger on the engine side is bent
slightly but enough for the oil to leak under pressure. You may want to
replace it if the new gasket didn't solve the problem and since you're I'd
suggest replacing the 2 little hoses too.

On Thu, Sep 2, 2021 at 6:39 AM Jon VonOhlsen <jondvo@gmail.com> wrote:

> Just finished a trip east to see family and friends. Was a total of
> about 5300miles over mostly highway. Some of the highways were pretty
> poor condition. Used 1/2 quart of oil, coolant dropped a little bit, I
> think it leaks through the front heater valve.
>
> the '90 Mulitvan has about 125K miles with the original engine, although
> I installed a 5sp few years ago. The van rides pretty rough on rough
> roads, road imperfections coming through like bangs. On smooth roads,
> not so bad.
>
> One issue that keeps arising is the oil cooler leaks. I have replaced
> and resealed this twice since I first got the van, and all is well for
> 1-2K miles and then starts leaking and getting progressively worse. Used
> the proper gasket, torque, etc. but still leaks after a while. Anyone
> else having this issue and any suggestions? The leak is more annoyance
> than anything but does tend to make a mess eventually.  Was surprised at
> the (lack of) oil consumption - using Motil 5w-40. I have used other
> 5W-40 oils and they all seemed about the same.
>
> Safe travels!
>
> Jon
>