Brown Sludge on Coolant Dipstick?

[Mikaelisu69]

Pulled my coolant dipstick out yesterday and noticed a brown sludge on the lower part of the stick. (5.7 hemi) Almost like a dark applesauce consistency.
Engine has only 16k miles.
I may have topped off the tank last year, honestly can't remember, with a standard Prestone coolant. Thinking this could be the cause?
Coolant temp runs normal at about 201 degrees.
Does anyone else have this brown sludge on their coolant dipstick, or did I cause this by topping off with a non-OEM coolant?

Just checked mine and it was completely empty with brown sludge on the dipstick. Only have 31,000 miles and had the engine replaced at 11,000 miles because it was using 1 at of oil every 1000 miles. Been to the dealer multiple times and assumed they were checking fluids but I guess not.

 

[HSKR R/T]

Fwiw my truck, with 75k miles has a completely clean coolant dipstick. I have had to top off my reservoir once because it was low enough dipstick was dry.

I also still get the coolant smell on hot shut down from time to time.

 

[Bigdumps]

Fwiw my truck, with 75k miles has a completely clean coolant dipstick. I have had to top off my reservoir once because it was low enough dipstick was dry.

I also still get the coolant smell on hot shut down from time to time.

Friends who rode in my truck said the same about mine, always said they smell coolant. Turns out my heater core was shot, then discovered my rad had a crack in it.

 

[HSKR R/T]

Friends who rode in my truck said the same about mine, always said they smell coolant. Turns out my heater core was shot, then discovered my rad had a crack in it.

You would be losing coolant if one or both were bad.

 

[KrustyKush]

This happened to me only two weeks ago. 2021 Laramie 5.7 non eTorque. While planning a 3k mile trip, I checked coolant level. Engine bone cold, sat overnight. I found the dipstick dry, with brown sludge gathered in the little holes on the dipstick, and along the sides. Before pulling the radiator cap, I ran down to nearby RAM dealer and bought a gallon of pre-mix Ram OAT coolant, and a new radiator cap. Back home, pulled the cap and found the coolant level up in the spout area, so not terribly low yet. The coolant had a brownish, opaque look to it.

I cleaned the spout area real good. I added enough coolant into the radiator to bring level up to the top of the spout. Then, installed the new radiator cap. Then, brought the level in the expansion tank up to mid-way between upper and lower, and went for a ride.

All was well. Completed the 3k trip without a problem, checking coolant level several times along the way. I must have ignored my coolant level for far too long. I won't do that ever again! Now thinking of taking her in for a system flush, even though only have 40k miles on it.

 

[sierracoco1]

For everyone who noticed the brown sludge and just added some extra coolant into the reservoir to get it back to the correc level. Has that taken care of the problem or have you found out it was something else. I have same issue on my 2021 Ram 1500 and don't want to have to bring it into the dealer if all I have to do is correctly fill up the reservoir.

 

[Trooper4]

For everyone who noticed the brown sludge and just added some extra coolant into the reservoir to get it back to the correc level. Has that taken care of the problem or have you found out it was something else. I have same issue on my 2021 Ram 1500 and don't want to have to bring it into the dealer if all I have to do is correctly fill up the reservoir.

Brown sludge most likely means you have a head gasket leaking oil(40psi) into the water jacket(9psi). There is an area in the head that is very narow between the two. I had the same problem on the drivers side, and had to replace the head gasket.

 

[Grape_Ape]

For everyone who noticed the brown sludge and just added some extra coolant into the reservoir to get it back to the correc level. Has that taken care of the problem or have you found out it was something else. I have same issue on my 2021 Ram 1500 and don't want to have to bring it into the dealer if all I have to do is correctly fill up the reservoir.

37k miles later for me and no issues.

 

[Morenar]

I reported earlier this week on another thread that I had the brown sludge on the dipstick and what look to be milky coolant. Took it to the dealer since I had extended warranty. They pressure tested and looked things over and said that the coolant fluid may have had water or non-approved coolant added. I told them the only people that service my truck when I need some warranty work is them. So either someone added windshield wiper fluid in the wrong place or someone added coolant but it wasn't me. So they are doing a coolant flush and removal of the coolant reservoir to clean it. Here are pics of the fluid in the reservoir.

 

[HSKR R/T]

I reported earlier this week on another thread that I had the brown sludge on the dipstick and what look to be milky coolant. Took it to the dealer since I had extended warranty. They pressure tested and looked things over and said that the coolant fluid may have had water or non-approved coolant added. I told them the only people that service my truck when I need some warranty work is them. So either someone added windshield wiper fluid in the wrong place or someone added coolant but it wasn't me. So they are doing a coolant flush and removal of the coolant reservoir to clean it. Here are pics of the fluid in the reservoir.

That fluid looks normal.

 

[Morenar]

That fluid looks normal.

Ok, good. Thanks for that. Guess the flush would not do it any harm other than my wallet.

 

[SD Rebel]

I reported earlier this week on another thread that I had the brown sludge on the dipstick and what look to be milky coolant. Took it to the dealer since I had extended warranty. They pressure tested and looked things over and said that the coolant fluid may have had water or non-approved coolant added. I told them the only people that service my truck when I need some warranty work is them. So either someone added windshield wiper fluid in the wrong place or someone added coolant but it wasn't me. So they are doing a coolant flush and removal of the coolant reservoir to clean it. Here are pics of the fluid in the reservoir.

That's always my fear of someone (or me) accidentally putting the wrong fluid in that expansion tank. The opening and cap looks like the washer fluid one, just on the other side, seems pretty easy to confuse and get them mixed up, especially a tech after a long busy day or me with my typically post 50 brain fade.

 

[Morenar]

That's always my fear of someone (or me) accidentally putting the wrong fluid in that expansion tank. The opening and cap looks like the washer fluid one, just on the other side, seems pretty easy to confuse and get them mixed up, especially a tech after a long busy day or me with my typically post 50 brain fade.

They usually have non techs when you drive into the service advisor bay to check in and they have the washer fluid fill bottles there that they use. They may have open the hood and topped off the wrong reservoir is my thought. About to buy a different color cap
Or sticker to put somewhere near it so they can’t mistakenly add it.

 

[SD Rebel]

They usually have non techs when you drive into the service advisor bay to check in and they have the washer fluid fill bottles there that they use. They may have open the hood and topped off the wrong reservoir is my thought. About to buy a different color cap
Or sticker to put somewhere near it so they can’t mistakenly add it.

That's a good idea, I typically don't have my truck serviced by the dealer, I do the basic stuff myself, but on the rare occasion I do bring it in and they throw in a service I think I'll just get some painters tape and write "NO" on it, and place it over the cap. I think I did that one time in the past, but forgot

 

[Morenar]

That's a good idea, I typically don't have my truck serviced by the dealer, I do the basic stuff myself, but on the rare occasion I do bring it in and they throw in a service I think I'll just get some painters tape and write "NO" on it, and place it over the cap. I think I did that one time in the past, but forgot

Same here. I only go in for warranty work. Do most services myself. Found these stickers on amazon but reviews say they don’t stick well. May just use some glue to have it stick to the plastic in front of the cap.

 

[SD Rebel]

Same here. I only go in for warranty work. Do most services myself. Found these stickers on amazon but reviews say they don’t stick well. May just use some glue to have it stick to the plastic in front of the cap.

That's cool, maybe use a little bit of painters tape to make sure they stay on, I would only use them for that day I plan at being at the dealership, take them off after.

 

[HSKR R/T]

They usually have non techs when you drive into the service advisor bay to check in and they have the washer fluid fill bottles there that they use. They may have open the hood and topped off the wrong reservoir is my thought. About to buy a different color cap
Or sticker to put somewhere near it so they can’t mistakenly add it.

There are literally pictures on the reservoir caps for what they are for.

 

[Morenar]

There are literally pictures on the reservoir caps for what they are for.

Yep, I know that but some young kid working the drive up may not look. Other cars like my wife’s Mazda washer cap is blue and coolant reservoir is yellow. That’s easily distinguishable

 

[TC5]

Coolant smell may be due to there being no clamp on the hose from radiator to overflow tank. I noticed my truck did not have a clamp on radiator to overflow tank, easy to remove when hot...so I added one. Do not notice coolant smell now.