Poor mpg after service

Tires? As in new tires? Or just rotated?

 

Could be the tires, different than what you had before? There's also the factor that any new tire will have higher rolling resistance. I suspect that's overblown though.

Check oil level too, some places are prone to gross overfill.

 

Unless my car has a noticeable or severe pull to the left or right, I never let them "sell me" an unnecessary alignment service when buying new tires.

I don't want anybody messing with my perfect alignment! 45 years of driving, with several cars, and I've had only ONE alignment in all that time. (Because I hit a curb.) And all my tires had excellent wear patterns!
Just my 5-cent opinion, but I think all those "alignments" are a $100 rip-off.

When I bring them 5 quarts, do those dummies NOT stop at 4.3, like the Prius requires? I think I'll pour out half from the 5th bottle.

 

Decades back, a little greener, I was getting new tires, and asked them to do an alignment check. They put it on the alignment equipment, and right away told me that everything was spot on, it wasn't worth doing, and no charge. Good place.

Our previous Civic Hybrid was similar, took 3.2 liters with filter change, and I'd talked myself into dealership service, it being near-new. As far as I can tell they routinely slammed in 4.0; they always handed it back with oil well over the full mark. That's when I said screw it, went back to DIY. Stuck with it from the get-go with our Prius.

FWIW our local Toyo dealership is pretty good in that regard. From what I noticed on a tour of the service department (during a "new owners night): they use bulk oil and graduated pitchers, use the spec'd amount.

 

I don't think those service guys like seeing that BIG 5-quart Mobil-1 jug that people like me bring in. It must be too heavy for them, or they don't use a funnel, they spill it, or whatever.

My Camry always smelled like burning oil for 3 weeks(!) after I had the oil changed at a couple dealers. (After 2 spine surgeries and disc removals/fusions, I'm unable to crawl under my Prius... but I sure wish I could do my own!)

 

how many miles on her, and what were the old tyres? it is said that alignment can affect mpg's, i'm not sure how much though.

 

new regular tires will do it. some of that will disappear as the new tires break in and wear out.
you should have purchased LRR tires.

 

Which Assurances were they? I see ComforTred, TripleTred, Fuel Max, just Googling.

 

what happen with the dipstick?

 

Service......air leak in/ near air filter.

Tire may be the best guess...so many threads on that.

Good luck finding the reason...let us know.