My parents have a 96 SLS that they bought in 98 when it had about 26k miles. Ever since they have owned it, it has been a pretty heavy oil burner (1 qt/500 miles). This may be due to the fact that it has always been truly babied. Later on, we became a 2 Northstar family (97 STS) and began to know more about the engine. We know the bit about WOTs and oil burning so when the SLS began asking for oil once a week (1 qt/150 miles), my dad started driving it to work. This trip gives him the opportunity to put it through its paces coming out of the tolls each day. This has been going on for 2-3 weeks now and oil consumption has not improved. A quart every 500 miles was bad but managable. A quart every 150 miles is crazy and a solution needs to be figured out. Are the rings stuck? Bbob?
Any help is appreciated.
04-08-05, 08:23 PM
A quart per 150 miles is a lot of oil....it should be puffing blue smoke. Are you always checking the oil level hot and not overfilling it...??
Putting a quart in when the DIC says "Check oil level"
04-09-05, 02:09 PM
Did you read thru this already.... http://www.cadillacforums.com/cadillac-tech.html#full
Well like I said, he's been running it hard on his daily commute for the past two weeks. What would you suggest, 10 minute runs at 6000rpm?
04-09-05, 06:47 PM
No, I would suggest the second gear exercise like I've mentioned many times before and in that discussion I referenced.
Heh, well I understand and I figured that's what you would say but the tough part is getting my dad to do it. Redlining it in first and then hard up till ~75 wouldn't be considered sufficient?
BTW - On another note, the car has also been known to make a little "crunch" when overdrive is engaged, and it is particularly noticable in 3rd gear. I'm almost positive the transmission fluid was replaced around 60k at the local Caddy dealer and it has still been making the noise for the past 20k miles.
04-10-05, 02:05 AM
Not to be a smart ass....but...if simple WOTs were enough I never would have wasted the time to type out an alternate procedure.
The oil consumption issue is usually aggravated on older, used cars that were babied around such that the rings are probably pretty sticky in the ring grooves and need to be freed up. The 2nd gear procedure of doing a WOT accel from 55 to 70 or so and then taking your foot off the accelerator pedal and allowing the engine to overrun with high vacuum with the throttle closed is designed to cause the rings to move to start to free them up. A heavy overrun like that at higher RPM makes the ring motion somewhat unstable...you have heard of "ring flutter" before maybe....so that extra part of the maneuver is really good for getting the rings to move and free up.