My experience has been similar. In my 1.8l I4, the oil temps rise in
response to increased hwy speed. "Normally" at 100 km/h and at 20 C ambient,
the oil temp reads 110C. Push the speed up to 70 and the oil goes to 120.
Drive up steep hill, van loaded, in 3rd gear, oil temps will hit 125.

Two other things affect this temp. First, and most dramatic, is the effect
of the sheet metal and foam rubber sound abatement shroud that is slung
under the stock diesel. Having this on raises oil temp 5-7 C over above
readings. I conclude from that that there is some oil cooling going on via
the aluminium diesel oil pan.

Second is that I have found that the coolant thermostat does have an effect
on the oil temps even at hwy speeds. I am running an 88 C Tstat right now.
When I switch to summer 82-83 C unit the oil temps will be roughly 5 C lower
than listed in the top paragraph.

Alistair
--
'82 Westy -> diesel converted to gas in '94
albell@uvic.ca
http://homepage.mac.com/alistairbell/home/

on 30/6/02 10:02 PM, David Marshall wrote:

> Only 220F (105C)?  Wow - that pretty cool.  The Audi 2.0L with a Digifant II
> head in my Syncro Multivan runs at 250F (120C) on the highway at 100km/h and
> can peak up to 265F (130C) when driving up steep grades in 3rd at 4500 to
> 5000RPM - I am measuring my temp at the oil filter flange.  20w50 Dino oil.
> Around town I may get up to 212F (100C) but on the highway where it has to
> work a lot harder the temps do go up.
>
> Anyone have a 'don't run higher than this' temp for Dino and Synthetic oils?
>
> David Marshall
>