VipinLJ

SkiingInABlueDream

StKnowhere

VipinLJ

I almost always drive it in S mode. But my wife and my brother, who drives it when he visits, don't. Plus they think the X3 feels more powerful in D mode compared to my car, because of faster responses and no DSG lag. That's why. I know my car used to respond better in D mode when brand new compared to now. Even in S mode, there's a slight delay compared to before when it was almost instantaneous. I know the transmissions are different in the A4 and my other cars (which have the ZF which I've begun to appreciate a lot more now).

HyperS4

(hijaking your question)MPG. As sporty as I like my car, Im mostly in traffic or on the highway cruising at a set speed. Im rarely in a position to be consistently in S mode. Ill pop it into S when I need to merge or overtake someone. Funny enough though, Every new car I get, I run the first tull tank with all Sport modes on. Break the car in with S mode on the transmission the whole time.

minmet

Isn't it in contradiction with most auto manufacturers' recommendation of easy on pedal and don't over certain speed (mostly around 60 mph) for the first couple hundred miles of break in period?

HyperS4

That has been debunked many times over. The biggest reason to take it easy upon break in has to do with the tires and brakes getting broken in, as well as you as a driver getting used to how the car handles. Why do you think you see so many crashed cars upon first 48 hours of ownership. Not that the engine wasnt broken in, its that they had no idea how to react to the way it drives. But thats a bit extreme honestly. To your question, tests have proven that an engine broken in under normal driving conditions, and one broken in with the limited RPM method, both broke in the exact same way. If youre going to romp on the car once its "broken in" and you did the baby break in method, thats like a shock to the system. Just drive it like you would normally drive it on a daily basis but take into consideration that the tires are still fresh and the brakes arent completely seated. Most engines come pretty much broken in after being tested on the assembly line anyway. Im not saying you should be red light racing right when you get your car, but you should be able to enjoy it spiritedly.

Even though this is for motorcycle engines, pretty much explains it

minmet

Surely quite lots of different opinion out there. Wondering where is the manufacturer's recommendation come from. Agreed that a new car breaking in is not just the engine, brake and others all considered.

HyperS4

Yup, and Im not telling anyone they should break in a new car any differently than they want to. I have broken in a lot of cars and motorcycles by driving the way I would normally drive right off the lot without any issues. Obviously giving careful consideration to the tires and brakes. Regarding the manufacturers recommendation, thats been around since the metal and technology in engines wasnt as good and you would literally have metal shavings in your oil pan at your first oil change in 1k miles. None of that happens anymore. They probably just leave it in for legal purposes to cover their butts. Thats just my guess.

SkiingInABlueDream

^^^ I guess either these theories is possible. But FWIW, both my A4 and the loaner I had were 2018's. But the loaner was a later production. But again, driving the loaner I remember thinking, hey this how my A4 behaved when it was new. And Im guessing that that loaner in a couple months won't have the same quick-to-downshift behavior that it did last week.

^^^ Tried this. I can't say I notice a difference, in S mode at least.

^^^ That's a really interesting video, but I can't say it convinces me that a hundreds or 1k of miles moderate driving break in is unnecessary. They don't address the question of how healthy would each engine be 50k or 100k miles later. I'd like to see a study using a large number of engines (large enough to be statistically relevant) where one group gets broken in typically (moderate load and varied RPM etc) and the other group gets run hard from the start. After the break-in, then drive all the cars in a caravan for 100k miles of everyday driving (ie not lapping a test track at 80mph constantly for two months), then study all the engines. Do dyno runs. Test for oil loss, do oil analyses, microscopically study the metal-on-metal surfaces inside the engine. See if any differences trend between the two groups. A simple experiment.