ok this started less than a week ago, while driving in any mode (sport) or other at around 45mph, trans feels like its trying to find gears between drive overdrive?? and then SLAP and then BANG it gets into gear with some nice grinding noise...what is it please anyone...never had a trans service, car runs great on the highway just around that 45 to 50 mph mark its terrible..any help / input would be appreciated, thanks

 

Could be related to the transmission or you could have a intermitient misfiring coil. I had a similar instance as the trans was going into OD - very rough (knew it wasn't the trans as I had it recently rebuilt) turned out the coil on Cyl #8 was misfiring intermitiently. After replacing the offending coil - transistion into OD - smooth as butter... Just my $0.02 - hope this helps point you in the right direction.

PS - This would be a great opportunity to get the trans serviced...

 

thanks abonano....would have never guessed it was the dreaded #8 coil pack, definitely feels more like the transmission...maybe rear axle bearing??? only
because of that grinding sound

 

Could "just" be low on trans fluid.

Hope it's a coil! Needn't be #8.

 

thanks jagv8, just got off the phone with a recommended independent jag repair shop, he just set me up for a Thursday morning appointment said its most likely transmission related, "don't drive far" and gave me a $550 quote for transmission flush / service. i hope it helps!!

 

I'm in NJ too. Could you please provide the name and address of the independent Jag
mechanic? Much appreciated. Also a follow up on your problem.

 

Pro Imports
309 Haddon Ave
Collingswood, NJ
856-751-9400

transmission fluid change was done, trans shift nice and smooth, no lurch, my fluid level was low ans dirty at 66k....but it still didnt solve the problem...going for the rear diff, axle bearings next...great repair service, jags all over the parking lot, phone ringing off the hook, 3 bays, jags in the air and on the ground getting worked on. busy place, hope its close enough to you.

 

Thanks, pretty much any reasonable distance is worth great service!!!!!

Good Luck with the dif.!!! You should read this TSB on the forum:
TSBs for 2003 S-Type (X200) V8-4.2L SC
Drivetrain - Rear Differential Replacement Information Jul 14, 2011 JTB001754

 

I see you have a bad differential, too. I have one in the shop that was cared for by the one owner and the car needs lots of work. Many problems.

 

How did we leap from a bang at a certain speed to needing a new differential?

45 MPH sounds like the torque converter lock up issue to me. There's TSB in the FAQs I think.

 

Mikey is spot on! Put the whoa brakes on here and let's not rush into things. $500 for a trans flush and swap? And ya still have problems? Though the indy Jag tech may have the phone ringing off the hook doesn't mean he's doing ya right. Jag doesn't require a trans fluid swap till 90k+ on the clock. I was thinking burnt torque converter. These are known to go bad on the 4.2 S.

 

yup i definitely needed the trans flush, car was sloppy shifting, notchy, lurching, just overall shaky drivability... local jag dealer wanted even more money and couldn't guarantee i would have the car back in the same day?? after hearing the noise after getting the car back, i called him back and he scheduled me back in next week suggesting possible rear diff, axle bearing but no mention of the TC. i called him again to suggest the TC he said possible but wont know until he gets it up in the air and drives it...can anyone point me in the direction of this TSB so i can review it...its just an annoyance until the car warms up that there is this noise around 45-55mph as if trying to find its gear and does so with a thud, usually going up an incline not with a heavy load and it always seems its while im turning right...i take the same route into work each day and it does it almost all the time at the same spot entering an inclined entrance ramp to i295 here in jersey...same holds true on the return trip home, same spot each time then never hear from it again...

 

In the TSBs. Look down for transmission growl.

 

I agree with Mikey.... Check those coils for an intermitient misfiring. I had the same issue when the TC attempted to lock up around 45 MPH... - it turned out to be a misfiring coil...

 

I already tried leading you in the right direction previously (Post #2)... be sure to have the coils checked. You might be very surprised.

 

coolhotblue, when not quite warmed up while driving, does the tach roam up and down by 200 rpm's? Then when at operating temp. the roaming tach subsides? If yes, then likely the torque converter.

 

bfsgross....i feel better if your telling me that's the symptom for a TC going bad....because my car isn't doing it.

 

this car no matter what it throws at me...squeaky steering , droopy headlights, noisy headliner, no dipstick trans, rear banging noises etc..... is always a joy to drive and appreciate. the information on this site is great but what makes it complete is knowing how much i appreciate everyone's help!!! thank you, i'm going to have the coils checked out tomorrow.

 

coolhotblue - I would say if you are by Bayonne, NJ (Exit 14A - Turnpike) - stop by - I have a coil tester and would be more than happy to check them out for you... feel free to PM me

 

Ok, then you may need new seat covers. LOL I don't know man, but I hope we figure out what's up with yer "S".