Guys
I have bought a beautiful '92 limited wiht 170k Miles or so a few weeks ago, In the past week or 2 I have been doing the usual checks and maint stuff, mainly fixing the head liner, filters fluids and so on.

I dont know what oil was in when I got her but I figured out to toss in some 5-30 as per specs to see if and how she would hold such a thin oil.

Now I drove some few hundred miles (like 4-500)
In 2 weeks without a spill. Temps are good fuel economy actually surpirsing, start up good.
But today I have noticed that if i lean below the car with the engine on idle i can hear some light clack clack which I kinda dont like... If I rev up It seems to disappear though... What could It Be? It Is really hard to notice when standing up.

I have a 10-40 valvoline maxlife on stand by ... Shall I put It in? ( Here in Europe 10-30 just doesn't exist )

 

One of the first things I would suspect would be loose flex platr to torque converter bolts. And check for any cracks in the plate. Fairly common for the bolts to loosen up a little

 

I had previously looked up for engine knocks and similar in order to diagnose... But HEY !!! I didn't come across this issue yet. I have found a video on youtube and THAT'S EXACTLY my kind of knock... I keep my finger crossed for the issue being only a loose bolt and not having cracks on the plate as I am completely broke right now and the spare itself goes for almost 200 euros over here....
Many thanks really

 

Hello, I have looked at my flexplate. seems all good.... I even tried to gently pry it with a screwdriver and doesnt tick or move...

 

Did you put a wrench on the nuts that circle the center of the flex plate? This requires turning the engine over by hand using the a socket on the crank pulley bolt.

 

Prying on the flexplate wont tell you anything as there are multiple bolts holding it on. Prying would work if they were all loose, but if just one is loose, that one bolt is enough to cause problems. Check them all. Sadly, cracks arent always visible without dropping the transmission. Sometimes they are, but not always.

 

Yup

 

Just to try to tick stuff out of my list Im going to go with a thicker oil today and I plan to run a seafoam treatment to see if somethig changes. If there Is the slightest change then ill know ain't the flexplate ...

 

I switched to Rotella 15w40 and wix filters for my 4.0 straight sixes. Seafoam is amazing but can be too good on an older engine...make sure to change that oil quick after using seafoam. It will pull out a lot of junk but some of that might be lubricating your engine by happenstance. I learned this from experience. Anyway....you should be good with a thicker oil. Also you can stop at 5 quarts and add a quart of lucas Oil Stop Leak...that stuff is like molasses. But you should be fine with Rotella. Just my 2 cents. And yes I have read hundreds of posts on recommended oils...it can get quite frustrating. Good luck!