If you drive a Toyota or Nissan and you’re due for an oil change, pay attention. Both automakers have quietly issued dealer bulletins rationing specific motor oil grades to their own service departments. This isn’t a rumor — it’s happening now, and it’s going to get worse before it gets better.
Here’s what’s going on, why it matters, and what you should actually do about it.
What’s Happening
Toyota and Nissan have both told their dealerships they’re not getting their normal oil allocations. Nissan dealers are receiving roughly 70% of their usual annual volume of synthetic engine oil. Toyota sent a bulletin in late April 2026 warning North American dealers of shortages in 0W-8 and 0W-16 Toyota Genuine Motor Oil.
Both automakers gave their dealers substitution guidance — meaning if they don’t have the right grade, they’re authorized to use the next step up for one service interval. Toyota’s guidance: substitute 0W-8 with 0W-16, or 0W-16 with 0W-20, for up to 20% of affected oil changes. One interval only.
That’s not nothing. That’s your dealership putting oil in your engine that isn’t what your manufacturer specified — because they don’t have what they need.
Why Is This Happening
The root cause is Group III base oil. Most modern “full synthetic” oils — the kind sold at every auto parts store and used at most dealerships — are built on Group III base stock. The problem is that Group III is refined heavily from Persian Gulf feedstock, and the Strait of Hormuz has been closed or contested for over 100 days.
US Group III supply is running at roughly a 44% shortfall. Wholesale prices have already cleared $10 per gallon. And the shortage isn’t expected to ease until mid-2027.
This is why your dealership might not have 0W-20 on the shelf. It’s why prices are going up. And it’s why the Group III oil sitting in most “synthetic” bottles at the store is suddenly a lot harder to source.
What This Means for You
If you’re driving a late-model Toyota or Nissan — especially anything calling for 0W-8, 0W-16, or 0W-20 — your options at the dealership are narrowing. You may get an approved substitute grade. You may wait longer for an appointment. You may pay more.
And it’s not just Toyota and Nissan. Those brands made the news because they issued formal dealer advisories. Every other brand running Group III-dependent oil programs is dealing with the same upstream squeeze — they just haven’t sent the memo yet.
Why PAO-Based Synthetics Are a Different Story
Here’s where it matters for your oil choice. Not all synthetics are built the same.
AMSOIL Signature Series is built on PAO (polyalphaolefin) base oil — a Group IV synthetic. PAO is engineered, not refined from crude. It’s a different supply chain, a different feedstock, and a different level of protection. It’s not caught in the same Group III crunch.
That’s not a sales pitch — it’s chemistry. When automakers are rationing Group III product and authorizing substitutions to keep service bays moving, that’s the supply chain telling you something about what’s actually in most “synthetic” bottles.
Application matters. If your engine spec calls for a thin oil like 0W-16 or 0W-20, you still need to meet that spec. But the oil inside the bottle — the base stock it’s built on — is a decision worth making intentionally, especially right now.
What You Should Do
- Don’t panic-buy. Shelf oil at auto parts stores is still available — for now. Buying 10 quarts you don’t need doesn’t help anyone.
- Know your spec. Check your owner’s manual for the viscosity grade your engine requires. Don’t let anyone substitute two grades up without understanding the implications.
- Consider switching to a PAO-based synthetic. If you’re already thinking about it, now’s a reasonable time. You’re not dependent on the same supply chain that’s tightening.
- Ask questions at the dealer. If they’re doing an oil change, ask what grade they’re using and whether it’s the OEM-specified grade or a substitution. You have a right to know.
The motor oil market is going through something it hasn’t seen in decades. This isn’t fearmongering — Toyota and Nissan both put it in writing. The shortage runs to mid-2027. Plan accordingly.
Questions about what your specific rig needs? Text SPEC to (651) 300-2010 and we’ll give you a straight answer.
Mill City Synthetics is an authorized AMSOIL independent dealer based in Woodbury, MN. Shop through our dealer link or text SPEC to (651) 300-2010.
