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Coolant overflow tank cracked?

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12 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHCoolant overflow tank cracked?

Leading reported evidence

Replace cap

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I did as you and replaced my cap with a newer one, but ultimately had to buy a new tank and did it myself.

Coolant overflow tank cracked?
Frequently discussed work

Replace both

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

it might not leak if the cap is not holding presure - replace both

Coolant overflow tank cracked?
Read full discussion summary

Leading evidence: 'Replace cap' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace both' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

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1 matching discussions · 12 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Replace coolant tank as a preventive

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I replaced my coolant tank as a preventive repair.

Coolant overflow tank cracked?

Replace earlier this year

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Mine had to be replaced earlier this year.

Coolant overflow tank cracked?

Replace just

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Had it replaced just before CPO was up.

Coolant overflow tank cracked?

Replace both

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

it might not leak if the cap is not holding presure - replace both

Coolant overflow tank cracked?
Frequently discussed actions (9)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Replace both

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

it might not leak if the cap is not holding presure - replace both

Coolant overflow tank cracked?

Replace cap

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I did as you and replaced my cap with a newer one, but ultimately had to buy a new tank and did it myself.

Coolant overflow tank cracked?

Replace coolant tank as a preventive

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

I replaced my coolant tank as a preventive repair.

Coolant overflow tank cracked?

Replace earlier this year

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Mine had to be replaced earlier this year.

Coolant overflow tank cracked?

Replace just

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed

Had it replaced just before CPO was up.

Coolant overflow tank cracked?

Replace tank

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

The shop wanted $750 to replace the tank.

Coolant overflow tank cracked?

Use digital thermometer

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

Get out and check that both radiator fans are running and blowing about the same amount of air out their exhaust vents and the air feels about the same temp (or use a digital thermometer to actually measure the air temp).

Coolant overflow tank cracked?

Use flash light and have a look see

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

The leak was very slow and very hard to notice but use a flash light and have a look see.

Coolant overflow tank cracked?

Use hands all the time

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

You might not be able to see the cracks but very good chance you can feel the residue build up, almost like small stalagmite (sp) I use my hands all the time to find a leak.

Coolant overflow tank cracked?
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

12 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • Rennlist: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

1 acknowledgements have no verified action link; they do not establish a repair result.

Outcome without a verified action link

Get it fixed.

No unique explicit quoted action; no causal link assigned

Generation: 20261026T024951Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hello, After I had my IMS and RMS upgraded the shop said I had a crack in my coolant overflow reservoir bottle. I asked them if it was not the cap "no we can see the crack". But no coolant leaks out after I got a new cap from the dealer. The old cap was a 00 last part # the new one is a 04. Shouldn't the coolant leak out of the crack every time I drive the car? I can't see a crack. The shop wanted $750 to replace the tank. The car is a 2000 c4 cab with 39,000 miles. Thanks, Cory in Reno

POST 2Original post

Mine had to be replaced earlier this year. 2001 C4 cab with 39K. Started leaking over my exhaust. Left a big pool of coolant everywhere when it decided to leak - no rhyme nor reason when it decided it was time to leak.

POST 3Original post

Very common unfortunately, to have a crack in the coolant reservoir. I did as you and replaced my cap with a newer one, but ultimately had to buy a new tank and did it myself. My tank at the time was $210.

POST 4Original post

I replaced my coolant tank as a preventive repair. Cost me about $400. If the tank looks yellowish, just change it

POST 5 / ORIGINAL POSTEROriginal post

Well I drove it up a two lane mountain road from 5000ft elevation to 9000ft in about 15 minutes. No one was in my way so I could go some what hard when I could. At the top in the ski resort parking lot(Slide Mountain) coolant was leaking out of the bottle. So if its driven hard up hill the bottle will leak but not on flat roads. I have a new coolant overflow bottle on the way.

POST 6Original post

Quotes source post: 8986556

You and the car were lucky the engine didn't suffer localized overheating and do some serious damage to the engine. If a coolant tank is suspected a better way to test is to drive the car around locally -- with the A/C off -- until the engine is fully up to temp and then back home in the driveway bring the revs up to say 1.5K or so. Hold the revs steady until you hear/feel the radiator fans turn on. Get out and check that both radiator fans are running and blowing about the same amount of air out their exhaust vents and the air feels about the same temp (or use a digital thermometer to actually measure the air temp). Once the fans shut off repeat the 1.5K rev step and this time when the fans come on shut off the egnine. The heat load build up will raise the coolant's temp and the cooling system's pressure and if the tank has a small crack, or even is just weak, you'll know it. And it is much more pleasant to deal with a serious cooling system problem with the car on your driveway than just about anywhere else. Sincerely, Macster.

POST 7Original post

Get it fixed. Sounds pricey though. There is a DIY on here or Renntech. I hear it's PITA though, but may save you $400 in labor.

POST 8Original post

it might not leak if the cap is not holding presure - replace both

POST 9Original post

Quotes source post: 8988649

Post #1 Ed...he did.

POST 10Original post

I replaced mine after looking under the tank and seeing a bit of white residue. I also noticed my coolant level was slightly low. The leak was very slow and very hard to notice but use a flash light and have a look see. Would have done it myself but I didn't wanna drop the motor. The gen 1 i believe is not necessary.

POST 11Original post

I had my car in for service, drove it home and noticed a pool of coolant near the rear tire. Took it back in, pressurized system, tank was cracked. Had it replaced just before CPO was up.

POST 12Original post

You might not be able to see the cracks but very good chance you can feel the residue build up, almost like small stalagmite (sp) I use my hands all the time to find a leak. If its really yellow change it out. Oh and do the water pump if you haven't done that yet...

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