I am driving from San Diego to Colorado Springs Thursday. I didn't trust the XJ40 I had a few years ago for a road trip that long.

 

Long trips are better in this car. My normal journey is 44 miles each way but I see no problem in doing 400miles in one go, very confident that it would be fine.

 

Last October I drove from Jacksonville Florida to Pittsburg, over to Philly then back to Jax, ran like a fine watch.

 

Napier NZ to Wellington NZ return - about 600km
drove pretty hard, averaged 25mpg on return run (XJR manual)

 

It's not the longest trip that I personally made, but it's the longest trip my car made. Long story short, a work colleague brought my car from Cobh in County Cork, SW Ireland up to me in Belfast. 270 Miles/435 KM. We had a coffee together and then I hopped in and drove back home to Kenmare in County Kerry, SW Ireland, 324 Miles/ 520 Km, so a round trip of 600 Miles/960 KM. And she didn't miss a beat.

Yesterday I did a round trip from Kenmare to Dublin, 226 miles/364 KM each way. That's 450 miles/ 730 Km total and I was pulling a 25' boat and trailer all the way back. She performed admirably. Maybe a wash and polish and a little bit of loving is due?

 

Adelaide to Canberra, Sydney, Melbourne, Adelaide with a number of deviations here and there.

Total of 4500kms.

Never opened the bonnet once.

Currently doing similar short run in the Black S Type.

FAITH, you must have FAITH. Worry less and enjoy that car.

 

Not sure when, but believe the summer of 2011; took it from DFW to Lexington, KY, down to Mexico Beach, FL and back to DFW ~2,500 miles, spanning 2 weeks - took some of the kids to see my folks then met the wife, with another one or two of the kids in-tow at the in-laws and joined her annual Beach-house vacay for several days. Did open the bonnet, but only to check the oil-level. Never had to add.

 

Two years ago with 4 people and the trunk full, Boston to Quebec city 600 miles round trip, this was before I had the steering sorted out, new steering rack this year. The engine and transmission are the two things I trust the most. It was a good ride, but not the many places to open it up, more speedtraps up there every year, even out in remote areas

 

Almost exactly two years ago, drove my 97 XJR back from Houston, TX to Sanford, NC... about 1200 miles over a weekend. Flew to Houston, bought it, jumped in the seat and drove it back. Zero issues.

It had 43k miles, now has 70k. Still no major issues.

.

 

My furthest was a circle trip from Calgary to California and back via the west coast and Vancouver Island, 10,000 km (6,200 mi) in 11 days.

That's where I found my endurance limit is about 1,600 km (1,000 mi) in a day, and only 1,400 km the second and subsequent days!

 

Took a road trip last July Kamloops B.C. to Lethbridge Alberta and return about 900 kms one way to visit family. Doing same trip again in about 6 weeks. Car is very comfortable on the highway enjoyed last years drive immensely.

 

Albuquerque to Nashville, 1500 miles, drove around a bit for 2 weeks and then 1500 back to Abq. All total approximately 4000 miles. Did that run twice in my prior '96 XJ6.
Also a trip from Santa Fe to Cabo Mexico and back, cannot recall those miles, was many.
91' XJS longest trips were: Knoxville to Albuquerque, approximately 1700 miles, and Santa Fe to Yosemite approximately 4000 miles.
Have yet to run my current XJR6 more than 500 mIles in a single day, but have no worries when I choose to do so.