OT: Slow coolant leak

[57stratdawg]

Any guesses? I don't smell anything in that cabin (heater core), don't see anything on the garage floor (water pump). It does feel like it has a slight 'shimmy' occasionally. Nothing incredibly noticeable, maybe I'm just being paranoid.

Pull the oil out and pray it isn't discolored?

Dealership pressured it see didnt see a leak.

 

[Dash Riprock.sixpack]

The make good radiator stop leak and your friendly neighborhood NAPA in Canton can help you. only big worry is leaking into oil and that will manifest itself with discolored oil.

 

[The Peeper]

The oil will turn a milky tan color if its in there

 

[MaroonNation]

Is it a Grand Cherokee with the inline six? The worst engine ever made by a "American" manufacturer.

 

[josebrown]

Check ur oil, make sure it ain't kinda milky. If you don't see any noticeable leaking areas around a hose connection, water pump housing or thermostat housing then I'd put a new cap on the radiator if u haven't. So long as u are sure about the heater core. Could be losing a little out the radiator cap when driving.

 

[Dawgbite]

Leak at the head gasket will allow it to seep into the cylinders and escape out the exhaust as steam. Cooling system is a closed system, if you are loosing fluid, its going somewhere. To check the head gasket, you will need to do a cylinder leak down test on each cylinder.

 

[T-TownDawgg]

^^ This. Head gasket/intake manifold small leak. If no milky oil, likely making its way into exhaust valve ports or exhaust manifold and evaporating.

 

[Dawgbite]

Is it a Grand Cherokee with the inline six? The worst engine ever made by a "American" manufacturer.

I'll have to disagree with this. I have been Jeepin for 35 years and have owned everything from a 57 to a 2012 and several 4.0 I6's and it is probably the best motor in a Jeep up to the current Pentastar 3.6L V-6. That motor was good for 200k miles and had gobs of torque. Trust me when I say, AMC put some real crap engines in Jeeps but the 4.0 wasn't one of them. You may have had a lemon, it just takes one to leave a sour taste in your mouth. You should have owned one of the AMC 4 cylinders.

 

[TheStateUofMS]

Check the Temperature Coolant Sensor. Easily located and if needs replacing very

Any guesses? I don't smell anything in that cabin (heater core), don't see anything on the garage floor (water pump). It does feel like it has a slight 'shimmy' occasionally. Nothing incredibly noticeable, maybe I'm just being paranoid.

Pull the oil out and pray it isn't discolored?

Dealership pressured it see didnt see a leak.

cheap. Maybe it just needs to be tightened.

I'm a car novice, so coolant leaking into oil sounds like a major problem. All I got is check the hoses and temperature coolant sensor. If the TCS is leaking, you'll know it.

I just changed mine on my Maxima...didnt' fix my problem, but I did get a code for it.

 

[jb1020]

Its easiest to check your coolant reservoir, see if its bubbly or has an oily look to it.

I don't think a pressure test would reveal a blown head gasket.

 

[MaroonNation]

This was a 2006 and I had to get a lawyer and threaten to take Wilson Jeep to court to get them to replace the engine. Even the mechanics said never get a Grand Cherokee with the Inline 6. They said the only engines that weren't problems were the V8's. They said the original design is from the 50's and Jeep replaced the iron block/head combo with a cast iron block/aluminum head and the engines never cooled right after that. warped the **** out of the head on mine just driving it up and down Lakeland to work.

 

[Digging dog]

Unfortunately this is probably head gasket. No leaks in pressure test, probably through exhaust valve.
What type of vehicle so we'll know what to avoid?****

 

[aTotal360]

Do you have a regular regulator cap or one with the hose that goes into a reservoir? I had one with the hose and it was cracked on the backside and didn't catch it for a while. Coolant was evaporating out and/or boiling out when it got too hot. I ended up putting JB weld on the crack and sealing it. They didn't sell the cap by itself. I'd have to buy an entire "kit" that was about $150, so I decided to fix it myself.

 

[Digging dog]

Duct tape and bailing wire.

 

[Shmuley]

Prepare the fetzer valve with some 3 in 1 oil and some gauze pads. And you will need about 10 quarts of anti-freeze, preferably Prestone. No, make that Quaker State.

 

[HotMop]

Is it a GTO? ***

 

[57stratdawg]

Yeah. I checked once to see if I could see any white smoke out of the exhaust, but didn't notice anything.

Having said that, my shimmy seems worse after it starts. Seems like after about 5 minutes it clears up. Wonder if it's leaking in there over night and that's what I'm feeling.

 

[57stratdawg]

Nah CTS. I don't think they have a great reputation either.

 

[stateu1]

Prepare the fetzer valve with some 3 in 1 oil and some gauze pads. And you will need about 10 quarts of anti-freeze, preferably Prestone. No, make that Quaker State.

It's all about ball bearings these days.

 

[xxxWalkTheDawg]

Is it a Grand Cherokee with the inline six? The worst engine ever made by a "American" manufacturer.

let me guess.. One of your problems was an oil leak from the rear main seal

 

[biguglyjoe]

This was a 2006 and I had to get a lawyer and threaten to take Wilson Jeep to court to get them to replace the engine. Even the mechanics said never get a Grand Cherokee with the Inline 6. They said the only engines that weren't problems were the V8's. They said the original design is from the 50's and Jeep replaced the iron block/head combo with a cast iron block/aluminum head and the engines never cooled right after that. warped the **** out of the head on mine just driving it up and down Lakeland to work.

Some of the 4.0s came with heads that had a casting flaw. This flaw would cause the head to crack. The engine itself has a good reputation for its durability outside of these years. The fix for this would be to replace the head with a TUPY head. You can remove the oil fill cap and look straight down. If you see letters TUPY, it has had the upgrade. Many 4.0s have gone 300K. I hate that you had a bad experience with yours.

I know this has nothing to do with the OP. I just wanted to drop that egg of knowledge on anyone that may be looking at picking up an earlier model Cherokee.

 

[msstatelp1]

If your radiator has plastic top, bottom, or side reservoirs, check them.

 

[T-TownDawgg]

In that case you may have an intake gasket leak. Pools up in the intake when you shut it off and it sits; then engine sputters trying to burn it out.

 

[57stratdawg]

That would leave clean oil, huh?

 

[T-TownDawgg]

Yup. You must be driving a GM.

 

[T-TownDawgg]

Ah just saw you have a CTS. Condolences. I'm no ASE mechanic but had experience with the notorious Dexcool GM uses. Some techs say that **** is the devil. And GM gaskets are crap. If you replace tell them to use FelPro gaskets or threaten to throw a **** kicking fit.

 

[engie]

I'm not sure which gm engine that is -- but I know a bunch of them had intake issues. Plastic intakes with egr sleeves too big/near the plastic. Would melt at that point and let coolant into the intake system. Outside of the slow leak, this can go indistinguished for 100k+ miles. Eventually it will get worse and manifest itself as an actual problem. Not sure I'd "fix" it before that point. Can do a lot of *** chasing on what you are describing -- and the wrong mechanic will leave you with more problems than you started with. Have done a handful of them...

 

[MaroonNation]

Some of the 4.0s came with heads that had a casting flaw. This flaw would cause the head to crack. The engine itself has a good reputation for its durability outside of these years. The fix for this would be to replace the head with a TUPY head. You can remove the oil fill cap and look straight down. If you see letters TUPY, it has had the upgrade. Many 4.0s have gone 300K. I hate that you had a bad experience with yours.

I know this has nothing to do with the OP. I just wanted to drop that egg of knowledge on anyone that may be looking at picking up an earlier model Cherokee.

The day I picked it up from the engine replacement we drove it to Gray Daniels Nissan and I left it there and brought a Pathfinder home. Never another problem

 

[MaroonNation]

let me guess.. One of your problems was an oil leak from the rear main seal

Strangely no. These are the problems I had with it

Coolant Low=was getting in my oil from the severely warped head

Brake switch needed replacing 3 times. Twice in same week

Air conditioning leaked all over passenger floorboard

Electric fan had to be replaced

Off all the power window motors that could have gone out in that ***** it was the passanger's side motor and assembly I had to replace.

 

[engie]

FWIW I've been directly involved in hydrolocking two of those inline 6's. Tremendous damn motors for the most part. Pull plugs, let starter blow oil out of the combustion chambers, replace plugs, and ready to rock and roll again. They will run upside down for awhile in my experience. Have seen one or two blown up too. Super easy motors to work on. There's a reason you can't find a TJ with that inline 6 under $10k for the most part...

 

[57stratdawg]

Yeah. My thoughts too. Seems like a wild goose chase in the intake/heads which may or may not end with something.

Ill pull the oil tomorrow and see what it looks like. Go from there.

 

[Crazy Cotton]

my 05 wrangler has 230K on that motor

One big problem with the 05-06 ones was they changed the oil pump drive to accommodate a change in the computer, so people get the dreaded "screaming monkey". I was really lucky, missed the change by a month (if you have an 05/06 with an S in the 8th VIN position, you're on borrowed time or you've already experienced loss of oil flow and a dead engine). consensus is they changed vendors on the ignition system/computer and this was an unfortunate fallout from that. I love the 4.0 from the earlier years - easy as snot to work on and all kinds of torque.

 

[MaroonNation]

Interesting. My 5.4L Triton in my F150 hydro locked once. Craziest thing I ever saw.

 

[ShrubDog]

I have put in over 350,000 miles in two 4.0's combined. Those jeeps never left me stranded from breaking down ever.

Had one submerged in a creek for an hour running, got a tractor to pull it out and kept on trucking.

 

[xxxWalkTheDawg]

I'm not sure which gm engine that is -- but I know a bunch of them had intake issues. Plastic intakes with egr sleeves too big/near the plastic. Would melt at that point and let coolant into the intake system. Outside of the slow leak, this can go indistinguished for 100k+ miles. Eventually it will get worse and manifest itself as an actual problem. Not sure I'd "fix" it before that point. Can do a lot of *** chasing on what you are describing -- and the wrong mechanic will leave you with more problems than you started with. Have done a handful of them...

GM series II 3.8 engines. If you have a Buick, Pontiac, or Chevrolet with one and haven't had the intake replaced.. You have a time bomb in your garage. It may leak with a drip, it may explode at once filling the cylinders with coolant, or anywhere in between.

 

[the dog is on the loose]

The "shimmy" your'e talking about would be an engine internal problem and not a leaking radiator, coolant tank or such. The shimmy sounds like a misfire in the cylinder. That would be coolant. If your just being paranoid and the shimmy your'e talking about isn't engine related then check for any brown discolored streaks coming from around the radiator. I had a gmc truck that once leaked coolant and couldn't smell it. After checking, I found where plastic side on radiator had a hairline crack. I had to use a telescoping mirror to see it. No leaks at idle but once truck was running on road and radiator pressure built up then crack would open causing coolant leak.