I gave the Monty it's first oil change under my care, and went to Mobile 1 5w30. I've used Mobil 1 in other higher mileage vehicles (this has 160k) and had good results. I was pleased to see my oil pressure is much stronger, but now when I take off from the first few stop signs, before the engine is totally warmed up, I get a nice puff of blue smoke that I never did before with the used up dino oil. I'm not *too* concerned -- it goes away once the engine hits operating temp, but I'm a little uneasy it just started all the sudden after the oil change.

I run 10w30 in my trucks, even a rebuilt motor I run 10w30. I would suspect valve seals are whats causing the smoke. not a big deal. 7 years of driving my own personal fog machine and zero problems. I fixed it just because I got tired of the cloud while offroading.

Yep. Mosquito-bishi was what they used to call mine on the trail. <img src="/forums/images/graemlins/lol.gif" alt="" />

Try a nice Rotella diesel 15w40 until you do them valve seals someday...

Just out of curiosity, what's your oil pressure usually read, if you know?

Thanks for the reassurance. I'm not too concerned, just thought it was odd to change the oil and instantly start having this issue.

90psi cold, 60psi running @3krpm, 20-30 idle warm with a mechanical gauge. 0-30 on the factory gauge at all times.

Great, thanks -- sounds about where I am roughly as well.

Drain the synth. Refill with 10w40 diesel dino oil plus a quart of dexron and run it for a couple hundred miles. Drain and refill with synth and report back.

Synth leaks easier than dino, so it goes past ALL seals and gaskets easier. The dexron will soften and swell the seals some which will delay the need to do a top end teardown. An added benefit is the high detergent level in the dexron which will clean some of the crud and sludge out.

Boy will it ever. Just don't leave it in too long.

Rotella T synthetic is good stuff. I use the non-energy conserving stuff in my motorcycle (better for the wet clutch) and occasionally the regular synthetic in my '95, although I'm partial to Mobil 1. BTW, my '95 does not smoke at 185K miles on the stock heads and valve guides/seals.

John B.

I have often wondered that about the dexron, my rear main starting leaking the last week think this might be a good way to get a few more months out of it?

Many of the high mileage motor oils have extra seal swelling compounds. Mobil high mileage synthetic has extra detergent to help clean the motor out.