Hi all, I am new to this forum and RR. I have a 2000 4.0 SE that I am going to attempt a head gasket replacement myself, because cylinder 7 is linking exhaust gas into the cooling system. I have done DIY work on other cars but never on RR.

My RR is also making the "ratcheting sound" under acceleration and have been told by repair shop that because of streched chain and possibly other stuff broken I need a new transfer case and need it very soon. Otherwise I'll break the transmission. I would greatly appreciate advise on the affects of bad transfer case on transmission and if a replacement is required ASAP.

 

It could potentially screw up the transmission, I've never head of this happening on a RR though. The chains do wear down after a given amount of miles and often need to be replaced. Its not a terribly hard job, just takes some patience. Download the rave service manaul from greenoval.com It will give you a break down of the engine and all of the torque settings needed on the bolts for the head gaskets job . Make sure you buy GENUINE! gaskets, I've seen too many posts where people use cheap knock offs to save a couple bucks. Only having to redo the repair 10k miles later. Before you tear into your transfer case, make sure its not the drive shaft making the noise. It is fairly common for the teeth on them to get worn out over time.

 

Is the racheting sound also vibrating the drivers floor board upon acceleration? I felt this when test driving a 02 RR HSE this past week. Maybe its what your mechanic said it was. I've never heard of a timing chain stretching. It's metal. Anxious to hear what the senior members think it is.
RROJ

 

I do not feel any vibration on the floor, its just racheting sound I hear under hard accelaration only when the windows are down. Like LRScott said, it is pretty common for chain in transfer case to stretch out and need replacement. My RR has 85K miles on it.

 

I just replaced my t case and there was only 81k on the vehicle. Just listening to your description, it's the chain in the case. I bought a used t case from a local shop for $500. Check out the reputable shops on rangerovers.net to see what they have in stock. If not eBay is a good source. Those cases can be as much as $2100 for a rebuilt one.

PS
Send out the head to a machine shop as a preventive measure.

 

Now I understand that a P38 timing chain can stretch and should be replaced around 80k.

 

Timing chain? I thought we were talking about the transfer case chain. I've heard of timing chains going out, but usually not until the whole engine needs to be rebuilt anyways. I know my chain is still original.

 

It is very rare for a timing chain to stretch on these engines. The rest of your Rover will likely be wore out long before the timing chain. I have heard of the transfer case chains going out however I have had 3 Rovers all with well over 100K miles and they were all on their original transfer case chain. I've never heard of the transfer case taking out the transmission when it goes. That sounds more like a scare tactic to me.

 

Ok, let me get this straight since I'm new and want to absorb everying there is to know about these quirky trucks. They have a timing chain that rarely goes but they also have a transfer case chain? I know what the timing chain does but what exactly does the transfer chain do?
RROJ

 

Most transfer cases have a chain that connects the gears (think of it as the chain and sprockets on a bike.) Some transfer cases use straight gears that mesh together rather than chains but they are rare. The chains just take the power from the input from the transmission and connects it with the output to the front and rear.