Good one.

 

I really thought I had this one nailed, folks. While the wheel bearing was definitely making noise, and it’s quieter now, the intermittent rumble strip-like sound returned and is getting more noticeable. It sounds and feels like it’s coming from the front of the vehicle, but both front wheel bearings are quiet, while the front differential/PTU remains quite noisy per the chassis ears.

I’m going to take it down to a local Land Rover specialty shop and have them quote me to rebuild/replace the PTU. It’s a job I don’t feel like tackling.

 

Check out freelanderspecialist.com. Might be cheaper to import a remanu from England.

 

So, I was just reading up on the PTU. Apparently, the splines are not lubricated at the factory (!!) when the unit is installed, so they are prone to rusting and corrosion, and the symptom is what you described, noise and rumble from the front. Maybe a clue for Sherlock?

An Aussie shop, Triumph Rover Spares, has them reman but they want AU$2750 for one of them. Woof.

The rebuild kits do not include anything to replace the parts with the splines.

AliExpress has them for $300-$500 depending on what link you click on. I'm not sure I would buy that.

This one is probably the best deal at a little under $1400 at the current exchange rate. A reconditioned and upgraded PTU/transfer box/front differential from the UK. You have to ship yours first and then they send you theirs, and you have to discuss international shipping charges. Since it's a repair it should not have to pay any tariffs if documented and declared correctly.

 

Call them directly, they excel in the customer service area from my experience. Or email...

 

Thank you, @flybd5 and @ThorInc

Very helpful information and perspective.

Thinking on this some more, the supplier landscape for this part has changed significantly since I last went looking. Evilbay has several vendors selling a brand new PTU unit compatible with the 2008 model year for $550, shipped. They’re not OEM, of course, but made instead by a company called BFO. China is the country of manufacture.

I have all of the tools I’d need to do the job and a well-equipped home shop to work in, so I’m thinking I might just tackle it. The local indy rover shop won’t use a part that’s not from one of their preferred suppliers, so I’d probably be looking at $2500 to have them do it. Doing it myself I could also replace some other bits while I’m in there, and still come out ahead.

https://ebay.us/m/UCdFXF

 

For that price and shipping, you can buy a spare and still have change left over! Nice find, their feedback is pretty decent.

 

Just to follow up on this, I decided to let the aforementioned local Land Rover indy shop have a look. They said they would be fine using the ~$500 Chinese-made unit if I was willing to forego their parts and labor warranty, to which I said "absolutely." But first they wanted to do a proper diagnostic at their shop, for a reasonable fee. When they called afterward, they told me they road-tested it extensively and could neither reproduce the problem nor find any evidence of significant wear (e.g. input shaft play beyond spec, etc). I expected this because I hadn't experienced the problem since the weather started getting warmer. Anyway, we agreed on a proper fluid flush and fill for the PTU, and I picked it up a couple days later. Now it's super quiet and smooth again - noticeably more so than before I took it in.

Note that I had previously added a few ounces of the proper factory-spec fluid to top it off as part of my own attempts to quiet it down a few weeks prior, but it didn't seem to help much. But now that all of the PTU fluid is new, it's silent again. I'll keep driving it as is and see what happens next winter. Lol. Thanks again for all of the input and ideas.

 

That sounds awfully familiar. On my 2003 Mercedes c240 wagon I've had some noisy thumping sounds on my driveline. i went to buy an extra set of tires and rims in CT and the seller had the exact same vehicle and problem, and the solution was to completely flush the tranny and torque converter and replace with proper fresh fluid. I just bought the entire kit to do the work, including the tool to pressure flush. I have a feeling I'm going to be signing the same tune as you...