Torque Converter for Transmission

[roryhinds]

Hi all

I've been told by the dealer that I need to replace my Torque Converter on my X5 2002 4.4i E53.

They recommend I replace the whole transmission which of course is crazy money at the dealer.

Does anyone know a good source for a Torque Converter and possible a complete transmission for my X5.

Any suggestions would be greatly appreciated.
Thanks in advance
Rory

[gixxerdoggy]

Just had my 03 x5 4.4 rebuilt because converter was coming apart. So after rebuild it still seemed to be something wrong so I had another new not rebuilt torque converter put in and that fixed it. It came from zf the company that makes the transmission. The vehicle doesn't accelerate the same but trans is perfect. The new converter is much heavier.

[RRPhil]

There was a total of nine different capacity torque converters specified for the 5HP24 transmission. Your ‘029’ transmission uses the SACHS WA4/W260 S-2GWK F38 model. This F38 model is also used in the L322 Range Rover. Incidentally, the ‘034’ transmission used in the 4.6is uses a different (larger) converter - the L51.

Phil

[jcorreanyc]

RRHill, that's great detailed info! I have an 03 4.6is that may be needing a new converter at some point. My SES light comes on from time to time due to torque converter lock up issues (although the car drives perfectly, can't feel a thing). Do you know why the heavier duty TC on the 4.6's are so prone to failure? I don't hear about nearly as many 4.4's having tranny issues. Any more detailed info is appreciated!

Gixxerdoggy, why is acceleration different with a new TC? Did they use a different part? Seems strange, please elaborate.

[gixxerdoggy]

The new converter looks nothing like the reman one. its heaver and looks nothing like the original one. ZF says that its bmw's software that causes alot of the trans issues were all experiencing. The converter never really locks up because they built in a 100rpm slip. This because bmw wants it to be a nice cruising vehicle and a sport utility that can perform or the wife can run to the store in..

[RRPhil]

ZF decided that they would try to save weight and space on the 5HP24 by not included a torsional vibration damper within the torque converter lock-up clutch. Instead, the lock-up clutch has a third mode of operation (in addition to ‘locked-solid’ and ‘off’) where it continuously slips at about 3% to absorb any torsional vibration in the driveline due to low engine speeds. In urban/city environments it spends a lot of its time in this mode. (Incidentally, this is the main reason that only Mobil ATF LT71141 fluid should be used in this transmission as the LUC slip characteristics are designed around the particular friction modifier pack in this fluid). On the Range Rover (same engine & transmission) the LUC never fully locks below 56mph - I dare say the E53 is similar. It’s interesting to note that when the 6HP26 was introduced ZF went back to incorporating a traditional torsional vibration damper in the TC.

On the L322 forums there are numerous references to the LUC causing vibration problems once the vehicle gets to 100k miles. I had my TC replaced at 103k miles for exactly this reason and when I took my old one apart the chatter marks could clearly be seen on the piston and impeller faces.



though the friction plate itself looked fine



Phil

[TiAgX5]

RRPhil, what are your thoughts on running the LT71141 Castrol Syn Multicar Import fluid in the 5HP24 trans? Some on this forum have stated it does not have the correct friction modifers to allow for proper trans life. FWIW, I drained/filled my trans 4 time with a filter replacement after the 3rd drain/fill. Did this at 100k miles and at over 160k now with no issues, even with towing a few +6000lb trailers for thousands of miles in the Texas and Florida heat (seen the OBC outside temp at over 120deg F several times in stop/go construction traffic here in Dallas TX).

[roryhinds]

what Torque Convertor would you guys recommend I replace mine old one in my E53 2002 4.4i?

Will there be any reprogramming required in the car computer or is it just a part swop out?

Is it a big job or can most mechanics handle the job?

Any help here would be appreciated

[gixxerdoggy]

Its a big job so pick your mechanic wisely.. get a new converter not a reman or you'll be in the same boat that I was.

[roryhinds]

thanks. Do you know of any good source to get a new Torque Converter from?