Ranges from 6°F to 112°F. Was thinking about switching to a 30 weight oil for the summer. Summers here are not mild, there are several weeks over 95 and a couple of days over 100. Plus all the stop and go traffic…
2021 Odyssey oil spec
- Thread starter MrStamper
- Start date
There is such a thing and it's constantly being confused with 'tighter clearances'. Presumably GM's issue is at least in part due to loose tolerances, not loose clearances.
OVERKILL
$100 Site Donor 2021
FWIW, there's nothing wrong with Chrysler's MDS, the MDS lifters don't fail. There have been QC issues with the lifters (ALL the lifters), same as with Ford on the 7.3L Godzilla, and some of the GM engines. GM has the added issue of having their AFM/DFM lifters internally collapse, which is not a problem the MDS lifters have.
My 98 5.4 Triton 2V specs 5-30, so did all the 2V mod motors before it.
OVERKILL
$100 Site Donor 2021
Yep, the Modular was back-spec'd to xW-20, while the HEMI was a bit more interesting, spec'ing both 5W-20 and 5W-30 depending on whether it was in an HD truck or not.
wemay
Site Donor 2023
This^
JHZR2
Staff member
Tighter tolerances are definitely a thing, like 50 years ago... Perhaps more recent is better machining with lower/fewer asperities that allows for a thinner hydrodynamic film being necessary to separate the parts. Add in better quality oils and you can definitely take advantage.
Whether you want to, the stress level of the engine, etc. all come into play…
JHZR2
Staff member
Thing is, that’s neither new or insightful. We’ve known that forever. Do it at your own peril or peace of mind. You likely won’t be able to measure the tangible difference objectively either way.
OVERKILL
$100 Site Donor 2021
And amusingly, things went the other direction on piston fitment, tolerances were loosened up (the allowable piston-to-wall clearance range grew) to allow for bulk-fit slugs rather than hand-fit. This, combined with short skirts, is how we ended up with a lot of engines with piston slap in the early 2000's.
I took the OP as taking a jab at the "tighter tolerances" error oft made when the person really means clearances, a myth that refuses to die. Bearing clearances really haven't changed much since the beginning, but per your point, an old 60's Windsor would have similar crank and rod clearance specs as well as their tolerance range to what we see today. What we DID end up with was far more rigid bottom ends, which was a necessary change to allow long-term durability on thinner lubricants.
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Concur, bearing clearances are based on journal diameter.
I switched over to 0w30 in both my 19 5.7 Hemi and my wife’s 18 grand caravan last year. Gained about 10 psi of oil pressure. Take it for what it’s worth, but the valve train on the van definitely seems quieter.
Inwas talking about the "tighter tolerance" or clearances not really being that tight.There is such a thing and it's constantly being confused with 'tighter clearances'. Presumably GM's issue is at least in part due to loose tolerances, not loose clearances.
I've been running 5W-30 in the Ram for a while now. I tow a travel trailer, and FCA seems to favor having the active grille shutters stay closed until coolant temps get up to about 230F. Oil temps can get up to 210-220F usually. Haven't noticed any change in oil pressure going to 5W-30, and I haven't noticed any decline in mileage. Last road trip out west it still easily managed 22 MPG highway. Who knows? It might be just fine with 0W-20, but it seems 5W-30 doesn't hurt anything either.
99 or 00 is when they switched the spec , IIRC.
For my 2000 Lincoln Town Car, 5w-30 was still specified in the owner’s manual. 2000 might have been the last year for the old green coolant, too.
Instead of 0w40, one could go out on a limb and use one of the many 5w40s that meet API SQ and ACEA A3/B4 down to minus 30C.
My issue with the variable pressure oil pump is the delay time it takes for the oil pressure to catch up to the engine’s requirement when the rpm is suddenly increased.
The 6.0 and 6.6L engines in the HDs without all the start/ stop cylinder dropping nonsense and same bearing clearances and tolerances as the 5.3s and 6.2s in the light duty applications last forever on 5w30 Dexos.
My issue with the variable pressure oil pump is the delay time it takes for the oil pressure to catch up to the engine’s requirement when the rpm is suddenly increased.
The 6.0 and 6.6L engines in the HDs without all the start/ stop cylinder dropping nonsense and same bearing clearances and tolerances as the 5.3s and 6.2s in the light duty applications last forever on 5w30 Dexos.
I know it is apples to oranges, Hellcat and Nissan GTR spec 0w-40 and the Ford Coyote a 5w-50. Not the main every day vehicle of course and cost way more, but man there sure are a ton of Hellcats around here. LOL
Plus I guess these were not needed to consider an approval for CAFE???
Plus I guess these were not needed to consider an approval for CAFE???
Well it is a “corporate average” fuel economy.
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