I wondered what is better a Jaguar Xj6 x300 4.0 or a Jaguar XJ8 4.0! ?. I have had 1 Xj6 x300 4.0 sport and a Xj6 x300 4.0. I have heard that the XJ6 is more reliable and less maintenance than the Xj8. I have a lot of bad stories about the XJ8. I have always wanted to have a V8. I have had v12 BMW's but never a V8 car before. Any help would be appreciated.

 

Having had both Mat they are two entirely different animals. I found the 4L sport to be a great drivers car especially with that straight 6 engine. The XJ8 on the other hand is much more refined and in many ways, elegant.

I had my XJ8 for 6 years and not one ounce of trouble but then again I do keep my cars maintained correctly.

 

My opinion.

The X300 with that inline 6, either 3.2 or 4.0 is the last of the REAL Jaguars.

They are sooooooo reliable, and do what they do without fuss.

The maintaining is simpler and a tad more forgiving.

A V8, WITH all the upgrades, trans, timing chains, water pump, thermostat, DONE, is more refined, as said, and being a later build would naturally be better in many ways.

Maintaining is special in many areas, engine oil, sealed transmission to name 2 off the top of the tired head, too hard for me.

An X300 every day, and if one of the 7 V12 versions on this island ever came up for sale at less than the National Debt, I would grab that in a heartbeat.

 

Having and had both X300 and X308, and in line with similar expressions, I think it can be summarized as 'feedback'.... The 300 let's you know what is doing more so than the 308 which is a bit more of a cocooned experience...On the inside the 300 feels a bit dated compared to the 308...I much prefer the door card and dashboard of the 308 with it's sweeping curves compared to the XJ40 interior notes of the 300 ....lets be honest, they had the 308 interior in the bag when they launched the 300 but holding out on customers is typically jaguar when it comes to design

 

From experience you will appreciate the extra power of the V8 (+50bhp on 4.0 litre engines), but the V8 is a thoroughbred, with all the , er, quirks that come with such beasts....

 

I would love the V12 6.0 myself but they are so hard to come by these days.

 

There are multiple threads on this topic here in the X300 forum, and I think even in the X308 forum and it seems to come up every month or two.... not that the question isn't valid and valuable

I'd suggest a quick forum search to get even more prior opinions.... but really to be fair, it comes down to personal preference, and perhaps cost as an X300 will be in most cases less expensive just due to age.

The performance of the two cars will be different as noted, but for example with the XJR the HP difference is about 48HP which is closed up by another + ~20HP (+ ~15HP rear wheel if I recall) if you add Andy's bracket based upon some cited dyno results. So the performance gap may not be that huge once some minor work is done to the X300.

I personally like the interior of the X300 better than the X308, however must admit that I am warming up to the X308 interior over time. Exterior between the two is a wash for me, although the front and rear X308 lamps(updating mine to X308 front now due one of mine breaking) are nicer, but I miss the side marker lights on the X308 being gone. Pretty minor nits really.

If you get the X308 XJR, the serious issues with the X308 transmission are moot as the X308 XJR gets the "bulletproof" Mercedes unit.

If I were in the market for an X308, I'd look for a 2003 XJR or Super V8 model, maybe 2002(not sure), as 2003 is when they sorted out all the engine issues from the factory (version 3 chain tensioners, metal thermostat housing, metal impeller water pump, other? I forget), has the re-engineered cupholder that doesn't break (seriously) and again has the reliable XJR Merc transmission.



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''If you get the X308 XJR, the serious issues with the X308 transmission are moot as the X308 XJR gets the "bulletproof" Mercedes unit.''

the 722.6

Unless you get an X308 XJR with a mercedes 722.6 box that has a bad valve body control module and plug......

these are electrical items....the plug on the gearbox housing connects the gearbox module to the valve body control unit....sometimes referred to as the conductor plate....both the plug and the control unit are known to get oil in them which in turn shorts out the connectors in the plug body and the solenoid connectors in the valve body control unit....and you get recurring limp home mode after varying degrees of driving...the limp home mode often disappears when the trans cools down, but it will continue to re occur until eventually permanent limp mode sets in

Its a PITA but you wont need to be a genius to fit a new unit and plug...just meticulously clean ...part will run you about £200 incl fluid ($300 ish) or double ans some for a shop to do it

How do I know this....uh huh

 

Good tip on the Mercedes transmission, although again to be fair this transmission is considered a peer to something like the GM TH400/4L80E from a durability and maintainability perspective.

This transmission doesn't have the not uncommon ZF drum failure issue as fitted to the NA (normally aspirated) non XJR X308s.

 

And the merc box does not have the PITA temperature dependant trans fluid filling procedure that the ZF has

But you are right....the 722 box is a very well engineered unit and a very smooth connected driving experience.