3.5 HT/HS enough to protect high mileage engine

[vxcalais]

Is a hths of 3.5 from a 5W40 oil sufficient enough to protect critical parts of a high mileage engine ? I know its not the be all end all, but if UOA are showing some wear from these areas (bearings, piston area etc), what is best level to get some life from the engine ???

It seems a good indicator of some oils where a thinner synthetic is equal or better in the critical areas than a thicker mineral or lower quality oil....seems interesting.

 

[TallPaul]

I would think HTHS of 3.5 should be sufficient for most any gasoline engine. A very robust Euro spec ACEA A3 requires min 3.5 HTHS.

 

[TallPaul]

Oh come on now. There are many BITOG members that should be chiming in on this topic, eh. Or should we direct him to the monster huge HTHS thread in teh other forum. Yeah vxcalais, you have to read this thread:
MONSTER HTHS THREAD

 

[Nederlander75]

Personally Id look for 3.9 or above for an engine I acquired with over 100K on it from expereinces Ive had. But, if it were my own from new knowing what I have learned for the good people here and my own UOA and research 3.5 would be my target. Im sure there are those here that would argue that nil difference exists between the 2, 3.5 and 3.9.

 

[afoulk]

Anyone know what the Ht/Hs is for GC? I have a hard time finding it for most any oil. Quakerstate is one of the few I've found that give you that in their specs.

 

[Nederlander75]

Its, at least 3.5, as it passes ACEA A3.

 

[vxcalais]

LOL, I am almost embarassed now that i asked this question, that thread it quite huge, i will go through it slowly. Thanks guys. It seems 3.5 is a good base. None of the oils are perfect as i read somewhere for 0 bearing wear it needs to be 16cp or something ???

 

[The Critic]

What kind of car is this for?

 

[vxcalais]

Buick 3.8 V6 - 1996 i think it is...

 

[DoubleDee]

In my GM 4.3 Vortec GC and M1 TSUV was very noisy with HT/HS of 3.6
I settled on M1 and Havoline at 3.1. UOA's were very good. I don't know this I6 in my Trailblazer yet, but after AutoRX I am going to try Amsoil 5W-30 at a 3.2 and do the UOA.

 

[BuickGN]

Originally Posted By: vxcalais
Buick 3.8 V6 - 1996 i think it is...


This engine will work fine with 10w-30 to 20w-50 in a normal climate. I remember reading somewhere that they like an HTHS of 3.4 or more.

My mother's Bonneville with the same engine has been on a straight 30wt for years with an HTHS of 3.5.

I would comment on what works in the turbo engines but there's enough differences to make it pointless.

 

[vxcalais]

Thanks guys, thats corrected one direction for me hehe

 

[PT1]

Originally Posted By: vxcalais
Buick 3.8 V6 - 1996 i think it is...


Forget the HTHS and just go with Maxlife syn blend 5w30 or 10w30 and don't look back.

 

[vxcalais]

Yeah Maxlife is only available here in 20W50.

 

[vxcalais]

Originally Posted By: Nederlander75
Personally Id look for 3.9 or above for an engine I acquired with over 100K on it from expereinces Ive had. But, if it were my own from new knowing what I have learned for the good people here and my own UOA and research 3.5 would be my target. Im sure there are those here that would argue that nil difference exists between the 2, 3.5 and 3.9.



http://www.pennzoil.com.au/downloads/tds/Pennzoil_Platinum_Synthetic_Euro_Formulation_5W-40.pdf

THis Platinum Euro spec looks the goods with a 3.9 HTHS.

 

[PT1]

Pennzoil YB 10w40 has a 3.7 which should do fine IMO. OR Castrol Magnatec 10w40 or Castrol GTX3 15w40 which has a 3.9 might be the trick and you should be able to get it where you live.

 

[sprintman]

For my BMW engine HTHS minimum is 3.5. Unfortunately most Americans on the BMW forums don't get it and just use any 5W30. Yes sludge is a major problem. When I point out their mistake they get very agro. I just don't get it?