Hi Steve

I'm with you all the way on this, if the rear end breaks away and you know how to steer out of it (which many people don't!) then you should live long enough to go and buy some new tyres for the rear.

Though if you lose grip on the front end and your steering goes, then you may not be needing to buy any tyres after all, in the event that you land upside down in a ditch!

 

I agree with that Doug

 

Great, that's all sorted then; absolutely everyone else is wrong and we are right.
Excellent!

 

It's a kind of surprising for me to see so many people claims new tires should be put on rear, for in Japan it is generally believed that newer tires should be put on front, whether it is an FWD car or a RWD car.

Especially when a front-heavy car like an XJS stops, as much as 70% of the car weight is on the front tires, so when the front is weak you won't be able to stop sooner.
In addition, when older tires slip and they are on the rear, you can still control the car with the better front, but when the older tires on the front you will just understeer and break into the outside of the corner.

So I would recommend the better ones be on the front.

 

It isn't so much as for stopping. The new tires on rear can keep you safe from blowouts or quick flats for control. Front tires if blown are uncontrollable. In high speed runs nothing can be controlled. But, if you are constantly burning rubber or squealing tires on take off, good tires on rear. All mechanical training does say new tires on rear for all AWD, FWD, RWD and 4X4 vehicles. This stuff is not written by dummies. Do what you want and let the lawyers decide later. Best is to replace all tires at same time.

 

Personally I think the front-vs-rear debate is largely academic. There are too many variables, the most glaringly obvious being how the driver reacts to any tire-related event, be it ordinary-ish loss of traction, the much more creepy hydro-planning, or a blow out.

If you do everything wrong it'll probably end badly no matter if the new tires were on the front or rear.

If you do everything right it'll probably end well no matter if the new tires were on the front or rear.

Cheers
DD

 

new tires on rear!


see the control?

 

It certainly looks that way to me, its not as if the rear tyres are bald, its just they are not brand new!

 

I agree with you 100% on that!

The more I think about it, the more I'm starting to realize that the 'Front End Nay Sayers' are wrong!

 

If I ever get a 'Blow Out' I for one don't want it on the Front!

 

Well said Doug!

I don't drive like a lunatic and am always mindful of the prevailing conditions.

 

Since I didn't 'Steal it', I don't intend to Drive it like I 'Stole it!'

Entertaining Video though, thanks for posting that.

 

OK, what I have not seen addressed here is the age of the tires you intend to keep. Your spare is not used, that does not mean that it is good. In general, any tire that is over 6 years old is suspect, and if over 8 years old, it should be replaced. If you are in the USA, see http://www.tirerack.com/tires/tirete...45:s&techid=11 to determine how old the tires are. Maybe you need 4 new tires to drive on, and can save that unused spare as a collectors item.

 

It 'looks' in perfect Condition to me and considering that today the price is over £100 I would rather gamble on that than an existing Tire with half the tread on.

I would be interested to hear what 'Steve' has to say as in a lot of respects it does appear that we are both swimming against the tide of popular opinion.

But in the event that 'Steve' says No, then I will have to reconsider my options in which case I would keep it as a spare.

 

If your spare is original, 1995, you should not use it as a road tire. You are risking a blow out.

 

If you had the money, would you not change your tyres (tires) as often as you changed your engine oil and filters?
I would for exactly the same reason as you change your oil at regular intervals; it's a consumable item that gets worse the older that it is.
If your spare tyre has spent 8 years lying on its side then it has spent 8 years lying in the wrong plane and then putting it on the car will alter its position by 90 degrees which can't be good: I suffer from this every time that I get out of bed!
Tyres are complicated; it's not just pouring rubber into a mould and coming out with a fancy tread pattern, there are complex chemicals involved which will deteriorate over time along with metal banding that will lose its structural strength.
It (to me) doesn't matter how powerful the engine is, how shiny the paint or how bling the interior is; the whole system relies on four contact points that are slightly bigger than the average footprint keeping you on the straight and narrow.
Front versus rear replacement? As previously posted the XJS doesn't have anti-dive geometry dialled in so when you tramp on the stop pedal there is a huge weight shift towards the pointy end which means a massive extra load suddenly arriving on the front footprints; the better tread there has got to be a good thing.
Crap tread on the back means that you will end up smoking the driving tyres more often which means that you will have to replace them anyway: but put the new ones on the front!
I vaguely recall that you were supposed to circulate the tyres around the car to keep the wear even but I can't remember if you were supposed to move them all one wheel to the left, one wheel to the right or swap them diagonally.
That obviously presupposes that all the tyres are the same size! Could be interesting if you ended up with one 245/45 on the left front and a 225/60 on the right front. Probably quite good for the Indy 500 but not so good for the Monaco GP!

 

Its worse than that its 1989!

 

My head is spinning more than my wheels!

But I think you are right! and wouldn't dare risk putting on tyres of two different sizes.

But I do remember watching an episode of 'Top Gear' where those guys in Iceland (That's the Country not the Shop) have a unique way to mend flat tyres.

By pouring Petrol round the rim (don't try this at home guys!) and having done so chuck a lighted match in!

I tried this on an Escort (That's a car and not some lady of the night!) That I 'Used to own' and much to my amazement it actually worked!

Just before the Petrol Tank caught fire and then exploded in my garden, which then set fire to a 20ft Conifer Tree.

Obviously I never bothered to call the fire brigade, unlike my next door neighbour, who did that for me, as he went into panic mode and thought my jolly jape would burn his house down!

Epilogue: We haven't spoken since! (I wonder why?)

 

I freshened up a V-12 once for a customer. Tune, fuel injectors cleaned, new fluids, wash and wax. He had just bought the car used and wanted it as close to new as possible. He bought his own tires, decent Pirellis. Upon leaving shop he was thankful for a nice running clean car. It returned on tow with all four corners beat to extinction. He was driving in the rain and got excited about running a Mustang that he forgot that the S can spin tires at a moments notice when the accelerator is punched and he spun on a Boulevard with plenty of trees and almost hit them all. So, not the rear tires actually hydro-plane a lot of the spin is from the V-12 power not being used properly.

 

I have a bit of an issue with the well thought out and apparently logically justified new tires on the front tendency. For those in the UK, the AA state new on the rear. Michelin state new on the rear. In the US, Tire Rack, Discount Tires the tiresafetygroup.com all state new on the rear. I could find nothing to the contrary.

At the risk of being somewhat controversial, the only place that advocates new on the front are posts in this forum. In defense of those with this view I'd be willing to bet that people in other car forums also harbor these opinions. Should it not be regarded as somewhat disturbing that all businesses that make their living from making or fitting tires advocate new on rear? I'd like to see some "official" support to the contrary rather than just "it stands to reason".

Finally, the only reason I am flogging this to death is that the industry consensus is that new on front is downright dangerous and I'm worried someone may get injured or worse. This does not seem to be a matter of opinion anymore, and it reminds me of the argument based on "I don't wear a seatbelt because I knew a guy who only survived a crash because he wasn't wearing one."