Blue/whitesmoke when retro shifting

[alfa59]

Hi,

Greetings from overseas Belgium (Europe)

When retro shifting with my M35A2 (having the LDT 465 1 C whistler turbo), there is quite some blue/white smoke coming out of the exhaust.
When getting back to speed, there normal (black) smoke.

What is causing this ?

regards,
Chris

 

[Angus1]

you will have to tell me what retro shifting is first.

 

[nk14zp]

Has it been sitting or not used much?

 

[Pawnshop]

Down shifting I suspect, oil blow by???

 

[jatonka]

I think it is oil going by the rings and or valve guides during downshifting, in my opinion. If you are not using an abnormal amount of engine oil for the miles you drive, I would say you are all right. If you have Marvel Mystery oil available over there, that added to your crankcase could help over time. Other readers, no need to flame me over the Marvel Mystery oil, I know some of you don't believe in it but I am older than dirt and it's always been good to my engines. JT out

 

[shootiniron]

Well said John

 

[alfa59]

Hi,

Yes indeed I mean down shifting. It has been sitting for 6 months, so no that long time. Just drove it 3 hours at 40 miles/hour. I was wondering if it couldn't be the "gaskets" of the turbo ? As when accelerating, I don't have the problem of blue smoke

 

[Barrman]

I agree with the just "drive it and see if any oil is even being used" advice. But, I have to ask. How can you even see the exhaust?

I had my top off mine for a while and except for the black when shifting up, I really couldn't tell what color mine was and I noticed the back ground terrain really messed up what I was seing. Did you see the exhaust or somebody in another vehicle following?

 

[alfa59]

Hi,

Yes I could observe it when following my truck from another vehicle. I was told by a mechanic he believes it is the "gaskets" of the turbo which are partly gone, resulting in when one down shifts, you create vacuum and as the gaskets are bad, it gets oil in and burns it.
Before looking to find a new turbo, I would appreciate some advice from our experts.

Chris

 

[OPCOM]

If you are downshifting to slow the truck, that is not recommended under normal conditions. An exception would be when going down a steep grade you would keep to a lower gear.

 

[50shooter]

If you are downshifting to slow the truck, that is not recommended under normal conditions. An exception would be when going down a steep grade you would keep to a lower gear.

I was not aware of this. I don't do it excessively but do try to slow it some w/the engine to conserve the brakes. Bad idea?

Sorry if this is a hijack but it caught my attention and am now worried/curious

Thanks
Jason

 

[Pawnshop]

As long as the rpm stays under the redline I don't see what the issue could be, I would much rather use the drive train to slow the truck than the brakes. I try to not use the brakes over 30 mph.