Dirty coolant dipstick (yellow sludge)

[426Cuda]

More likely transmission fluid mixing with the coolant in the radiator...

Ummm not sure how that would happen Ron?

 

[kleanphil]

Isn't the trans oil cooled in the radiator ,maybe a hole in adjacent parts could allow it to mix , but it is yellow , i would assume a pinky or brown colour if that was the case . The last time i had sludgy yellow in the rad was a crack in the block or head , allowing sump oil to mix with the coolant or in my case water cos i never used coolant in any of my cars untill now

EDIT: No sorry , from memory it was the actual sump oil that was a yellowy sludge

 

[monty_vfssv]

I noticed the yellow sludge on my coolant dipstick and syphon tube when changing my LS3 cam at around 4000kms. But coolant passages were clean as a whistle so didn't worry about it too much. Might try a waterless coolant next time but need to do more research on the stuff.

 

[426Cuda]

Isn't the trans oil cooled in the radiator ,maybe a hole in adjacent parts could allow it to mix , but it is yellow , i would assume a pinky or brown colour if that was the case . The last time i had sludgy yellow in the rad was a crack in the block or head , allowing sump oil to mix with the coolant or in my case water cos i never used coolant in any of my cars untill now

EDIT: No sorry , from memory it was the actual sump oil that was a yellowy sludge

Yeah. On cars without a trans cooler, the trans fluid runs through pipes in the bottom mb tank. But, I've never heard of one splitting and mixing with the coolant. Doesn't sound impossible though.
As you say, creamy sludge in the radiator, or the engine, or both, is usually a blown head gasket. That said, it seems this small amount of yellow slime in the coolant tank is due to the coolant reacting to plastistcs? As noted by Skylarking and Immortality. Out of interest, I've not seen this on any of our private or work VF's though.

 

[Skylarking]

In the older 70’s and 80’s Holdens, autos were cooled by running a pipe through the bottom of the brass/copper radiator. In poorly maintained cars, it was not uncommon for this pipe to corrode and then allow water to mix with the transmission fluid killing the auto in the process.

With the improvements in vehicle design, this seems to not occur so much these days. Whether it’s improvements to materials, coolant or both, I don’t know, but I still don’t like the idea of cooling the auto fluid via pipes running through the engine coolant radiator. It’s simply a cheaper solution than having a separate oil/air radiator dedicated for the purpose of auto fluid cooling.

Me, I’ve never had auto fluid leaking into the coolant radiator so can’t say what the coolant would look like but I’ve had coolant leak into the engine where the oil ends up like capachino froth with similar froth in the radiator, all due to a blown head gasket.

In any case, if DexCool may still cause seal damage due to the OAT additives, so any oil in the coolant system, any coolant leaks or any plastic going gooey could be likley be due to that known OAT seal/plastic munching mechanism that was the cause of the class action. Alternatively, GM may have simply made a batch of coolant dipstick out of crap plastic that just won’t last?

Meanwhile, checking for combustion gasses in the coolant due to blown gasket is a rather simple and cheap test one can do. Not sure if there is a similar test that checks for the presence of engine oil or auto trans fluid in the coolant?

 

[panhead]

Yeah. On cars without a trans cooler, the trans fluid runs through pipes in the bottom mb tank. But, I've never heard of one splitting and mixing with the coolant. Doesn't sound impossible though.

Everything is possible, you only have to mention ‘Milkshake’ to the Ford boys and they start to shudder.

They have a well-known problem where the heat exchanger which is hooked to the coolant lines fails and the transmission oil mixes with the coolant writing the trans off.

To get around it they fit an external air to oil cooler.




.

 

[VFSSBlackLS3]

That can happen with 3.8ltr holden V6s... My mate nearly lost his trans as a result of trans fluid and coolant mixing in the radiator of his VT

 

[dgp]

Just as a point of reference to the OP, I have a 2016 October built VFII Redline nearing 50k km’s on the clock and checked my coolant dipstick today, it is perfectly clean.

 

[monty_vfssv]

Just as a point of reference to the OP, I have a 2016 October built VFII Redline nearing 50k km’s on the clock and checked my coolant dipstick today, it is perfectly clean.

interesting.. anything on the rubber hose that sits inside the coolant reservoir??

 

[chrisp]

I just had a look at mine. It’s an October 2016 Redline with about 33,000 km on the dial.

The coolant dipstick has a slightly yellow deposit on it...

The yellow seemed to wipe off quite easily with a single wipe....

The coolant itself seems to be clear like water.