Just a odd problem after last two oil changes I have had oil/smoke coming from vent in front of gearcase cover.Seems to go away after 1k miles. I use 10qts 15w40 rotella and 2qts of lucas additive.I run 60psi at idle warm and 85+ under power.So am I missing a potential issue here or is this normal fer a 98.5 with 151k?Any ideas to fix this would be appreciated.Bill

 

smoke from the case vent is usually blow buy but that would be constant smoke. has the truck had a hard life or is it a grandpa kinda truck?

 

The stock crankcase vent is poor at the best... I came up with a fix for it... I'll send you a PM...

 

Well, if it stops after 1,000 miles, then there is no basic engine problem. Therefore there must be a problem with what you are putting in it. Rotella does not do this. I'm betting it's the Lucas.

Large amounts of additives can upset the oil chemistry. I run no additives and never have. I see no reason for them and I have never had an engine problem.

NOTE: For those who use synthetics, they are known for causing problems with flat tappet engines. Our Cummins engines are flat tappet engines.

 

Well the first 100k were grampa rv miles the last 50k have been climbing mountains pulling a minimum of 3500 lbs and 14000 lbs at times.I have kept up on maintainence and expect 300k out of it.I had a 6.2 go 211k and sold the engine after putting two trannys in.Power is good and the level on stick stays up between changes just turned 1200 miles since last change and oil is starting to darken and smoke has stopped.maybe a vent change and dropping lucas will help.We use the lucas in our heavy trucks some have over 1million miles without a major overhaul.thanks for replies,Bill

 

What type of problems come from synthetics?

 

To give you piece of mind I would send in for an oil analysis to Blackstone. It only costs @ $20 and you will be able to sleep at night. I've run at least one on every vehicle I own (gas too) and it's nice to know that all is well.

 

I did, and they (Amsoil)gave me the thumbs up.DTR is awsome but can cause a little paranoia.

 

That Lucas is junk...

I used it in my 360 and burned oil like crazy...

Stop using it for a while...

Those little demo gears with the additive in them is false advertising...

I'd love to see it bond at 250+ degree oil temps...