I have a 2004 Land Rover Discovery II 4.6L with 65,000 miles on it. In the past month it has started to make a tapping/chirping noise when I accelerate especially uphill. No noise at idle or in neutral. I researched this on the forum and immediately replaced the front drive shaft with a greaseable rebuilt one from Great Basin Rovers. That did not fix the noise. I replaced the serpentine belt and checked the tensioner and all of the pulleys for worn bearings which were all working smoothly. I had a mechanic put the truck up on a lift and with the transmission in drive and the brake on the noise can be reproduced by stepping on the gas (around 1100 rpms and above). The tapping/chirping speeds up as rpms increase. The mechanic used a long-handled screwdriver against different parts and his ear and was not able to locate the sound specifically. He also sprayed soapy water around looking for leaks (valve covers & hot exhaust manifolds) but didn't seem to find anything specific. After about an hour of no solutions he said it is probably a head gasket leak we were hearing and it will be very expensive to fix so you should start looking for a used engine online (that changing the engine would be cheaper than a head gasket!). I think he was just trying to get me out the door because he was stumped. There is a very small amount of oil and dried coolant on the underside of the engine but I have never had any on the ground and have never had to add either in two years, other than changing the oil. No misfires and other than the tapping/chirping which seems to be getting louder the truck seems to run ok. It is driving me crazy. I am concerned something is being further damaged. Any ideas?
I have a sound recording of the chirping I can email if anyone wants to hear it.
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
Last edited by adamstennett; 11-24-2012 at 08:28 AM.
Reason: added more information
Checked for combustion leak this morning with the blue fluid block tester kit from auto zone. Ran the test and the fluid stayed blue. No leak. This seems to indicate that my head gasket is ok. Also checked the valve cover bolts and snugged them 1/8 of a turn or less. There is a little oil around the oil filter. I checked that it is snug and it is. Should I try changing oil to a heavier weight like 15w40? Right now I have castrol edge w/syntec 5w30. Last oil change they almost put 5w20 in but I stopped them.
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
Last edited by adamstennett; 11-17-2012 at 12:37 PM.
Crawled under and checked all the gaskets in the exhaust system with a leather glove on this morning. Doesn't feel like anything is leaking. Did notice there are triple gaskets between the manifolds and the engine on both sides. Someone must have been trying to fix something there at some point in the past. (I bought this truck two years ago with 57,000 miles). Sounds a lot like a belt even though it still chirps with the serpentine belt off. Sprayed the new serpentine belt with belt conditioner today just to be sure and hit the bearings of all the pulleys with wd40. The chirping seems to be getting louder each day. Sounds like I have chipmunks on a wheel under the hood. Any ideas would be much appreciated.
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
Have you rebuilt your front drive shaft yet, if it only had 1 grease fitting, then it needs to be rebuilt.
You can remove the front shaft and drive in high lock to see id the noise is gone.
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Mike
Retired service manager, member of Solihull Society, SCLR, NCLR and the Santa Barbara 4Wheelers clubs.
99 D2, 3" lift, CDL with Detroit,T.T. lockers, 4:11's,H.D. axles, custom ft/rear bumpers with sliders, a 9500 HSI Warn winch and 5 HID's.
Replacing the front drive shaft with one from Great Basin Rovers was the first thing I did. It also makes the noise when the truck is not moving. (in drive with one foot on the brake and the other giving it some gas) Any other ideas?
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
Last edited by adamstennett; 11-19-2012 at 07:12 AM.
It now makes the noise in park and neutral over 2000 rpms. (seems to be happening easier and is getting louder?)
Also checked for a loose spark plug but no luck.
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
Last edited by adamstennett; 11-20-2012 at 07:13 AM.
Did a smoke test and have no exhaust leaks.
Also did a compression test.
The noise seems to be coming from the passenger side near the back two cylinders/head gasket. There is a little puff of white smoke from that area if you really rev the engine. Can also feel a little puff on your hand if you put it down there.
Compression test on the passenger side is 120 on each cylinder.
Mechanic says it is a leaky head gasket. $2,000ish parts and labor.
Any reason to get a third opinion?
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
Exact same numbers on every cylinder seems very unlikely, but taking those numbers at face value... doubtful you have a blown HEAD gasket on that side. Keep looking deeper, maybe intake gasket leak.
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1967 Camaro LS1
1977 Corvette LS1
2000 Discovery II (No LS1)
Still trying to engineer an LS(X) into a Discovery II
I said the same thing to the mechanic. He said the first time they tested #6 it was 90 but he rechecked it and it was it was 120 just like the other 3 on that side. I thought they were supposed to be up around 150-170? Thanks. I'll look at the intake gasket.
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
Does anyone else think this might not be a head gasket?
I did a combustion test on the coolant tank that stayed blue.
Compression test was 120 on each cylinder on the passenger side where they say the head gasket leak is. No sign of coolant in the oil and have never overheated.
Two mechanics have said head gasket but I'm not sure I'm $2,000 convinced.
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2004 Land Rover Discovery II 4.6L V8 with 65,000 miles
may be silly but did he have all the plugs pulled when he did the test?
i'm not sure about the hg idea either.. typical hg failure would be either external fluid leak or external combustion leak (sounds kinda like a puffy exhaust leak)
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Tapping chirping noise under load - head gasket?
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