I am slightly concerned that SM rated oils do not have enough zddp for a 98 Jeep 4.0 engine. Currently I have 10W-40 Castrol white bottle in there. It is SM rated. It gets around 0 degrees around here so I figured no higher than a 10W. Possibly just go to Rotella CJ-4/SM or is that equally low on ZDDP. Any SM oils that can get an SL level of ZDDP?
Jeep 4.0 engine running with SM rated oil?
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I may be wrong, but I think that one of the requirements of SM is a reduced level of ZDDP from SL.
Do you really need it in your Jeep?
I have read that it is an issue with flat tappet lifters.
Doesn't the 4.0L have hydraulic lifters?
The SM DOES have antiwear additives, just different.
There are still oils out there that have the ZDDP, Redline being one...although that is $$$.
As for Viscosity, I would stick with what the owner's manual calls for (or other similar documentation).
I looked up '98 Jeep Wrangler with 4.0L motor on the Amsoil Website and they list 10w30 oil for above 0 degrees F.
They also list a 6.1 Quart oil capacity with oil filter change.
If you have a different Jeep......check the Amsoil website, if you don't have a owner's manual as they have some very useful information......and they have good products that you can get through one of our Amsoil sponsors here.
Do you really need it in your Jeep?
I have read that it is an issue with flat tappet lifters.
Doesn't the 4.0L have hydraulic lifters?
The SM DOES have antiwear additives, just different.
There are still oils out there that have the ZDDP, Redline being one...although that is $$$.
As for Viscosity, I would stick with what the owner's manual calls for (or other similar documentation).
I looked up '98 Jeep Wrangler with 4.0L motor on the Amsoil Website and they list 10w30 oil for above 0 degrees F.
They also list a 6.1 Quart oil capacity with oil filter change.
If you have a different Jeep......check the Amsoil website, if you don't have a owner's manual as they have some very useful information......and they have good products that you can get through one of our Amsoil sponsors here.
Dude your '98 is fine for SM. If you can't sleep about it use an HDEO 10w30 or 5W40. It is really unnecessary though. Your jeep is tough and the It will run on almost any [censored] you put in it. Trust me, I had the same vehicle and trashed it (not changing for 10K+ on quik lube oil) and that thing had over 230K on it when I traded it in for the cash for clunkers deal and it would have probably run much longer?? That was the only question + I had no AC in Florida (I still miss that thing). I am much more conscious now, but just trying to make a point. DON"T worry about ZDDP unless you have a classic car or something with rebuild engines with flat tappets from china.
sm oil is just fine in that engine...i think 10w40 is to heavy for the winter and if that was one of our engines that we build i would ask the customer to use 5w30....
we see a fair share of motors here that are here because of heavy oil in the winter
use what the manual says they designed and built that engine they could be on to something..
we see a fair share of motors here that are here because of heavy oil in the winter
use what the manual says they designed and built that engine they could be on to something..
Manual (not my friend Manuel) says 10w30/10W-40...
I'll stick with what I've always run in 4.0's from now on (haven't owned one since way before oils went downhill), which would be what is on sale at the parts store!
I'll stick with what I've always run in 4.0's from now on (haven't owned one since way before oils went downhill), which would be what is on sale at the parts store!
I was concerned about the lowered levels of ZDDP used in my Jeep 4.0L.
No flat cams are turning up on the Jeep boards I frequent.
The guys running Crane aftermarket cams were having problems but it was caused by the cam lobes that were much narrower than the stock cam lobes.
The 05 and 06, 4.oL's are eating oil pump drive gears and this is caused by a production change where they eliminated an oil hole. Not caused by using SM oil.
No flat cams are turning up on the Jeep boards I frequent.
The guys running Crane aftermarket cams were having problems but it was caused by the cam lobes that were much narrower than the stock cam lobes.
The 05 and 06, 4.oL's are eating oil pump drive gears and this is caused by a production change where they eliminated an oil hole. Not caused by using SM oil.
SM rated oils are perfectly fine for a stock 2.5L, 4.0L, or 258ci Jeep engine.
I ran Quaker State Q-Torquepower 5W30 in my trail Jeep last year during a trip to Moab. The engine saw constant 2000-2500 rpm cruising around in compound low. I even rolled in one of those "hot-tubs" too. No ill effects.
I just pulled apart a 4.0L that I'm rebuilding for my daughter's XJ. It's a Renix 4.0L from '89. The cam and lifters looked great.
While I do run SAE30 or 10W40 in my Jeep engines during the summer, I switch to 5W30 for winter.
I ran Quaker State Q-Torquepower 5W30 in my trail Jeep last year during a trip to Moab. The engine saw constant 2000-2500 rpm cruising around in compound low. I even rolled in one of those "hot-tubs" too. No ill effects.
I just pulled apart a 4.0L that I'm rebuilding for my daughter's XJ. It's a Renix 4.0L from '89. The cam and lifters looked great.
While I do run SAE30 or 10W40 in my Jeep engines during the summer, I switch to 5W30 for winter.
Originally Posted By: wiswind
I have read that it is an issue with flat tappet lifters.
Doesn't the 4.0L have hydraulic lifters?
The 4.0L has hydraulic flat tappet lifters.
I have read that it is an issue with flat tappet lifters.
Doesn't the 4.0L have hydraulic lifters?
The 4.0L has hydraulic flat tappet lifters.
hey thanks for the spelling lesson im glad you were able to understand me anyway...the owners manual should say 5w30 with temperatures below 61 degrees.. i just looked it up on all data and the castrol motor oil site and they both agree with me its 5w30 in the winter..10w40 is too heavy in the winter and can in some cases cause oil starvation, bad gas mileage and rob some of your power..And i dont know of any oils that went downhill...Are you talking about sa rated oil that is on sale at the parts store or sn rated oil because sn has the best ratings so far.
Originally Posted By: EarlyPorsche
Manual (not my friend Manuel) says 10w30/10W-40...
I'll stick with what I've always run in 4.0's from now on (haven't owned one since way before oils went downhill), which would be what is on sale at the parts store!
Do you want help or do you know everything?? It sounds like you know all you WANT to know. Maybe, read and learn what you NEED to know. Those oils are on sale because it is wintertime and they are obsolete. There is a thing called progress, and you need to know that happens (in some cases). Fuch's Oil, for example, is one of the finest oils out there and "designed" for performance cars mainly in Europe, it has hardly any Z., P., S., Moly. So the base of an oil is very important. Today's base stocks are much better and thus can be supported by lesser more efficient addy packs. You can put all the ZDDP you want into a garbage oil and you are going to have an unhappy engine. Go with a 5w30 most recommend Shell, Mobil, whatever. Don't just start being rude with just 4 posts.
Manual (not my friend Manuel) says 10w30/10W-40...
I'll stick with what I've always run in 4.0's from now on (haven't owned one since way before oils went downhill), which would be what is on sale at the parts store!
Do you want help or do you know everything?? It sounds like you know all you WANT to know. Maybe, read and learn what you NEED to know. Those oils are on sale because it is wintertime and they are obsolete. There is a thing called progress, and you need to know that happens (in some cases). Fuch's Oil, for example, is one of the finest oils out there and "designed" for performance cars mainly in Europe, it has hardly any Z., P., S., Moly. So the base of an oil is very important. Today's base stocks are much better and thus can be supported by lesser more efficient addy packs. You can put all the ZDDP you want into a garbage oil and you are going to have an unhappy engine. Go with a 5w30 most recommend Shell, Mobil, whatever. Don't just start being rude with just 4 posts.
Originally Posted By: chubbs1
Originally Posted By: EarlyPorsche
Manual (not my friend Manuel) says 10w30/10W-40...
I'll stick with what I've always run in 4.0's from now on (haven't owned one since way before oils went downhill), which would be what is on sale at the parts store!
Do you want help or do you know everything?? It sounds like you know all you WANT to know. Maybe, read and learn what you NEED to know. Those oils are on sale because it is wintertime and they are obsolete. There is a thing called progress, and you need to know that happens (in some cases). Fuch's Oil, for example, is one of the finest oils out there and "designed" for performance cars mainly in Europe, it has hardly any Z., P., S., Moly. So the base of an oil is very important. Today's base stocks are much better and thus can be supported by lesser more efficient addy packs. You can put all the ZDDP you want into a garbage oil and you are going to have an unhappy engine. Go with a 5w30 most recommend Shell, Mobil, whatever. Don't just start being rude with just 4 posts.
Don't be silly, when oil goes on sale all the weights go on sale. You misread my post as well: what my statement said AGREED with all others that basically ZDDP doesn't matter and therefore any oil in the proper weight will work.
Originally Posted By: EarlyPorsche
Manual (not my friend Manuel) says 10w30/10W-40...
I'll stick with what I've always run in 4.0's from now on (haven't owned one since way before oils went downhill), which would be what is on sale at the parts store!
Do you want help or do you know everything?? It sounds like you know all you WANT to know. Maybe, read and learn what you NEED to know. Those oils are on sale because it is wintertime and they are obsolete. There is a thing called progress, and you need to know that happens (in some cases). Fuch's Oil, for example, is one of the finest oils out there and "designed" for performance cars mainly in Europe, it has hardly any Z., P., S., Moly. So the base of an oil is very important. Today's base stocks are much better and thus can be supported by lesser more efficient addy packs. You can put all the ZDDP you want into a garbage oil and you are going to have an unhappy engine. Go with a 5w30 most recommend Shell, Mobil, whatever. Don't just start being rude with just 4 posts.
Don't be silly, when oil goes on sale all the weights go on sale. You misread my post as well: what my statement said AGREED with all others that basically ZDDP doesn't matter and therefore any oil in the proper weight will work.
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Originally Posted By: EarlyPorsche
what my statement said AGREED with all others that basically ZDDP doesn't matter and therefore any oil in the proper weight will work.
ZDDP does matter. It's the amount of ZDDP required for your application that is the issue.
IMO, flat tappet cams with STOCK valve springs appear to still live long lives on SM. That has been my experience. The aftermarket cams are typically the ones to suffer (and being aftermarket, may have higher pressure valve springs).
When it comes time to fire up the rebuilt 4.0L for my daughters Cherokee, I will still add a ZDDP supplement for break-in. With stock springs, I will switch back to SM (or SN by then) oil for daily driving.
what my statement said AGREED with all others that basically ZDDP doesn't matter and therefore any oil in the proper weight will work.
ZDDP does matter. It's the amount of ZDDP required for your application that is the issue.
IMO, flat tappet cams with STOCK valve springs appear to still live long lives on SM. That has been my experience. The aftermarket cams are typically the ones to suffer (and being aftermarket, may have higher pressure valve springs).
When it comes time to fire up the rebuilt 4.0L for my daughters Cherokee, I will still add a ZDDP supplement for break-in. With stock springs, I will switch back to SM (or SN by then) oil for daily driving.
The 4.0 is a very low stress flat tappet engine and there is no issue with the newer oils.
thank you chubbs,Zaedock and Eddie i agree with your thinking besides those 4.0 engines are pretty much bullet proof
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