Hi guys,

Been meaning to post this for a while, but it's been a hectic school year and Jag issues have taken a 'back seat' to exams and papers. Hoping you can help me troubleshoot the issues I've been having with the transmissions in the VDP and the XJR-100.

'99 VDP - 196,000km:

When it's cold outside (which is always in Canada between November and April) the car consistently shifts hard into 2nd gear - but only the first shift after starting. I could drive 100 ft, make the car shift into 2nd and it would shift hard - but if I immediately stopped and started from 1st again, it would shift smoothly into 2nd with no issues. Wondering if this is because I'm running Dex-III trans fluid as an alternative to the Jag-spec stuff and it doesn't like the cold temps. My first inclination is to flush it and re-fill with the Jag-spec fluid and see if this remedies it.

'02 XJR-100 - 188,000km:

Similar issue, only with the XJR it's both wildly inconsistent and worse. With no rhyme or reason (it could happen twice in one day or not happen at all for a month) the car will bang into 2nd gear so hard that it kicks the TCS on. It's been doing this since I've owned it - about 1 year and doesn't seem to get any worse or any better - just likes to boot me in the *** every once in a while when shifting into 2nd. I'm thinking this might be a sensor or solenoid of some sort that I could replace? This one I'm less sure about.

Questions/comments/concerns/criticisms? As always, your feedback is appreciated

David

 

There's literally thousands of threads all over the internet on the Daimler ZF trans. It sounds like a worn valve block with a solenoid sticking, research the TransGo kit and get it fitted before theres further damage done (pressure spike from sticking solenoid breaks a circlip and the A drum outer edge gets destroyed, leading to rebuild or swap).

Less so on the Mercedes AMG trans in the 100 as its build for way more torque, the funny thing is the ZF weighs about twice that of the AMG...
I would search the forum for info on the one main issue with the AMG trans and that's a leaking seal that transfers fluid in and up the loom connected to it, this may well be your fault on this car.

 

Not an expert here, but the first one, wrong fluid I would say.

Second one, I think you are correct about the solenoid, if I recall it's not an uncommon issue on the MB transmission. I read a full explanation of the problem on this forum about a year ago, don't remember the details but a search should turn it up.

Some more knowledgable will hopefully chime in...

Edit: I just saw Sean's comments. I installed the TransGo valve in a ZF 5hp24 a couple of years ago and it did in fact improve shifting. Definitely not a bad idea...

 

Hi Sean, sorry to hit you up for more info on this, but you've forgotten more about X308s than most of us will ever know. I searched the forum (maybe I wasn't doing it right) for more information on this but came up with nil. Is there a tech bulletin or diagram you could direct me towards that might detail this particular seal and/or loom? Would give me something to look for or mention to the shop when I take it in. Your assistance is appreciated as always.

Cheers,

David

 

Sure, the 'umbilical cord' or main transmission loom goes through the floor and the connector twists onto the transmission. There are 2 o ring seals on the connector, if the seal isn't doing it's job then fluid leaks out and capillary action draws it up the loom, causing trans issues.
Once under the car it's plain to see. If it's a mild leak, a cleanup and new o ring should sort it, if it's saturated (and you'd probably see some fluid on the floor, then a new loom maybe in order.

 

That is actually a myth.

The ZF 5hp24 as in the X308/X100 is a lower spec version. Not all 5hp24s are set out for lower torque figures. The same tranny is used in the Audi S8/RS6 just with 2 additional clutches in the rear drum. The rest is the same.

The 5hp24 can technically take in it's base configuration 430 nm on the inputshaft. With the additional clutches (like the 5hp24A has and as can be retrofitted to the Jaguar version), it can EASILY take 550 nm (like with the S8 W12) and if you tweak the turbos on the RS6 (C5 model) it can take more than 700 nm without changing anything. And in some cases (as in the case of my tranny expert, who did my 5hp24), it can take more than 1000 nm from standstill!

Just because Jaguar chose to take the "lower spec" version, just like BMW did, doesn't mean the tranny can't take much. The 5 speed Benz tranny can, in adapted version, take 1000 nm, but only with power reductions in lower gears. The 525 nm of the XJR/XKR are technically "nothing" for the 5hp24 in full spec.

Oh, just to clear things up: the XJR and XKR does NOT have the AMG nor the Speedshift version of the 722.1 transmission. That was introduced in 2002/2001 So it is just simply the 722.6 5G Tronic

Just to clear things up

 

Many thanks. Appreciated as always, Sean.