Auto gearbox upchange

[Aristocat2009]

Hi guys,

I've very recently bought a 1991 4.0 XJS. It generally runs superbly but I've noticed that the upchange from 1st to 2nd gear can be a bit abrupt. If I accelaerate rapidly it is quite noticable - if I accelerate gently it is hardly noticeable. Is this normal?
Regards

Chris Thacker

[dhdove]

Aristocat
Welcome to the XJS forum
I noticed your other post re idling and Surrey Jag Center found gearbox fluid low..........this would have been my first port of call re poor change quality.
I think if you take the car for a test drive now you may , hopefully find that both faults have been cured.
If not come back. BTW just HOW LOW on fluid was the gearbox, and.....where did it go?
Regards
DH Dove

[Aristocat2009]

Aristocat
Welcome to the XJS forum
I noticed your other post re idling and Surrey Jag Center found gearbox fluid low..........this would have been my first port of call re poor change quality.
I think if you take the car for a test drive now you may , hopefully find that both faults have been cured.
If not come back. BTW just HOW LOW on fluid was the gearbox, and.....where did it go?
Regards
DH Dove

Many thanks for a speedy & helpful reply.

[brian696]

Ive just gone through the same saga in my XJS 4.0 celebration 1996 - ZF249E box - ended up having to have a complete rebuild. (4 weeks ago)

Same initial symptoms - then gradually took longer to engage on start up followed by rough gear change.
Tried to salvage by replacment filter and fluid change but too late - damage was done.
Eventually total failure with no drive.

Report from rebuild said damage was burned out pump and two clutches.
Reasons for failure were basically lack of maintenance AND USE.

Bought car with 30K certificated miles recorded - only done 2K miles in the last five years and only 200 miles in the last three years.
Full service history stamped book by local Jag specialist ?? What a find!!!

Key points made by Gear box specialist:

Critcal on the ZF boxes is the filter - usually not changed by garage mechanics because they never look dirty - but they are and essentially must be changed at every two years regardless of mileage. Most failures are caused by this neglect.
A blocked or inefficient filter starves the pump of fluid and eventually leads to overheat and burn out of pump and clutches which is what happened to mine. Also lack of use and old fluid causes fluid break down which in turn contaminates the filter

The clunky change is usually caused by sticking valves in the valve chest - the first sign of problems - this may be rectified before total failure if seen to ASAP. (without g/box removal)

Following my rebuild I have to replace the filter after 3 months or 1K miles to meet guarantee requirements.

I had quotes for rebuilds from £2k to £1200 (total job)
chose the £1200 job and got a two year no quibble guarantee -all the others were 12 months guarantee.
The most expensive quote was JDHT at £2830 for exchange only!

Moral of the story - GET IT SEEN TO NOW because it will only get worse.

hope this helps

BC

[ptjs1]

As Brian has eluded to, I would suggest that the first thing to do when experiencing problems with a ZF box is to change the fluid and filter.. and then change the fluid again. It can cure a host of problems.

Brian, just to clarify, XJS parts are not sold by JDHT. It's just a link on their website. It's Jaguar Classic Parts, a divison of the Unipart organisation who have responsibility for sourcing and distribution of XJS parts. And although their quote was £2800, it was a brand new gearbox, wasn't it?

Welcome to the Forum, Aristocat, and good luck with sorting out your stalling problem. You'll find plenty of people willing to offer advice (..or sympathy!) here.

Regards,

Paul Sinnott
XJS Registrar
Jagauar Enthusiasts Club

[brian696]

Paul
Checking the notes I made whilst getting quotes for the box fix the deal from Jag Classic Spares (Glyn Parks) was actually £2851 + Vat and it was "exchange".
I assumed it would be a new box and I had to return my old unit after it had been removed.
I did not receive a written quote as I spoke to them directly on the phone so I cannot confirm my assumptions.

[ptjs1]

Brian,

You're correct - it was new gearbox that they were selling, but because of the shortage of units for future reconditioning, they often sell only on an exchange basis for your old unit.

I suspect that the route you took was the best value overall. I'm glad it worked out. Hope the car is now performing well.

Paul

[poprivet]

I had to replace my HP22 gearbox two or three years ago, luckily they are also used in the XJ40 so a 2nd hand one didn't cost a lot. However recently on occasions, on selecting D from neutral there would be a delay before engaging. On the way to the MOT a week ago, it also took a long time to shift up from 1st, so today I replaced the filter and fluid (got about 5 litres out of the 8 litres total)
I was suprised just how much rubbish the magnets had collected and how dirty the fluid was in just a short time.
Everything now working normally again Oh, by the way, it passed the MOT without any problems!
When was your filter last changed? could be cheap insurance.
Pop

[dhdove]

Pop
New MoT and no snags!
Many Congrats Another years motoring stretches ahead......
DH Dove

[Gordon@1962]

After reading all the posts I think I'm going to take some time out and change the oil and filter on my box too. (not sure which model it is??)

I've noticed that on the very odd occasion if its extra cold in the morning it won't change up from 1st to 2nd.
But as soon as I back off the throttle a bit and then accelerate again it fixes it. Then it'll be fine for another few weeks or so.

[Aristocat2009]

Since posting my query I've had the filter and fluid changed in the auto box and this has helped. Whilst cold the upchange from 1st to 2nd is slightly noticeable but once warmed up it is resonably smooth. I don't think that the auto box fluid or the rear axle fluid have been changed since new so having had both replaced I think that this was well worth the cost.


Blessings,

Aristocat