What types and years of vehicles have weak rings?

[JWC86]

EFI was what extended engine life.

Why do you think that was? EFI doesn’t wash down cylinders as bad?

 

[Marcozi]

The BMW M54 engine (2.5L and 3L versions) had low tension oil control rings. That was exacerbated by smallish oil return holes in the piston lands. Those holes would slowly get blocked, resulting in oil burning. The only solution was to doing piston soaks.

 

[road_rascal]

Our 2009 Saturn Aura XR 3.6 never consumed any oil during the 124k miles we've had it. Old 2001 Windstar 3.8 maybe needed 1/2 qt at 5,000 miles when we sold it with about 160k miles. Old 1999 Taurus 3.0 24v did start using about a quart every 2,000 miles after about 100,000k miles (traded in at about 125,000). Current 2018 Equinox 1.5 and 2012 Rav4 3.5 still doesn't use oil between changes.

 

[SC Maintenance]

I've never had a problem with it in the 80s or 90s cars. Did the rings get even weaker sometime after 2000? It's usually cars made after 2000, and especially after 2006 or 2007 that I hear about having serious oil consumption beginning at shockingly low miles. At what point/time did it become a serious concern?

Yes, and some vehicles never have problems - including ones with low tension oil rings. Thats the point. Its engine specific.

 

[supton]

Why do you think that was? EFI doesn’t wash down cylinders as bad?

Yes, on cold start, less fuel. Also better mixed, as it was sprayed under pressure, not some big squirt from the accelerator pump during starting. And once running, quick to get into closed loop, and running whatever "optimal" A/F ratio.

Carbs can be close, but once they get out of tune... plus cold start seemingly always put some amount of raw fuel down the intake.

Now this helps with cylinder wall wear. Which I'm guessing wore rings too. But I'm not sure what impact it had on rings gumming up with carbon.