Ims And Rms Failure On Mkii 996S

[cg962]

Dear all,

any idea whether the rms and ims problem is less prone to occur on mk ii gt3 engines?

I have noticed a low speed knocking sound especially going up and down steeper hills at low speed and am wondering whether I should be concerned.

My car had just been serviced with all engine and g'box mounts replaced

Any ideas?

Thanks

cg

[clord]

Hi CG.... As you probably know, out GT3 engines are a totally different engine from the 'usual' 996 engines. It is the 'usual' engines that have most of the reputation for RMS and IMS seal failures. That said, the 996 GT3 engines have experienced an unusual number of RMS seal leaks/failures. It's been hard to predict which/when a GT3 RMS will leak. For instance, mine is original and not failed (fingers crossed). A friend had a GT3 that was just 2 serial numbers younger than mine and his failed at least three times. All replacements were completed under warranty.....then, he sold it.

As for your low speed knocking, I'm not sure what it might be. Can you be more specific? Does it happen when turning? When engines is pushing? as opposed to on overrun? Any tire flat spots? Are the CV joints sound?

Let us know what you find.

[cg962]

Hi clord

last time the car was on a ramp there were no signs of oil leaks, the sound is definately from the rear axle/engine at very low speeds going uphill the car is absolutely fine at speed...

Actually having consulted with some local gt3 owners it seems the rhd vehicles are not prone to rms problems for some reason but most of the local cars are rs models, perhaps we do have a milder climate out here.

The sound is a clucking noise and other than that the car runs fine

thanks

cg

[clord]

You may be hearing the limited slip differential. It's audible at low speeds, when turning slightly and going both forward and backward with a gear engaged. If it is that, you can diagnose it by putting it in neutral and letting it coast forward or back at low speeds. The sound will not be present if there is no forward nor rearward drive to the diff from the gearbox. The diff then just acts like an open (non limited slip) diff. Let us know.