I know what lifters are, but thanks for the info.......his question was "Are our lifters roller or flat tappet". You answered about the rockers.......

 

I asked about the lifter style (flat or roller) because my '84 Dodge RamCharger has flat hydraulic lifters and my '88 Dodge PowerRam has roller hydraulic lifters. I used Comp Cams Engine Break-In Additive for the last oil change on the RamCharger (Mobil 1 10w-30), but just use the Mobil 1 10w-30 without the additive in the PowerRam.

I didn't know what style lifters my '96 and '99 Cherokees had. Since I now know that they are the flat style, I'll be using either the Comp Cams additive or, more likely, Lucas' Engine Break-In Additive, which was recommended in another thread.

Thanks for all the information!

 

All jeep 4.0L are Hydraulic Flat Tappet. Not a roller tappet.

Tappet is another name for lifter

 

Who is this directed to?????? Not sure what you guys are reading or replying to but I know what a lifter, tappet, rocker, pushrod, roller cam, flat tappet cam is...............

 

My question without reading this entire thread is this...is there an additive that will add the needed Zinc?

 

ZDDP, search for it on ebay, lots of info on it...........

 

There are several:

COMP Cams® Engine Break-In Oil Additive Extends Engine Life
New COMP Cams® break-in lubricant provides missing additives no longer found in current motor oils

Time marches on... and generally that’s a good thing. But unfortunately, over time, some of the good stuff can get left behind. COMP Cams® Engine Break-In Oil Additive brings back the good stuff, delivering a specially engineered blend of extreme pressure break-in additives that have been removed from current off-the-shelf motor oils. Delivering added protection during the break-in process and beyond for all engine components, including the camshaft and lifters, COMP Cams® Engine Break-in Oil Additive is compatible with any petroleum, synthetic or blended motor oil.

COMP Cams® Engine Break-In Oil Additive extends the durability of internal engine components, protecting against premature camshaft, lifter and valve train failure. Best of all, COMP Cams® Engine Break-In Oil Additive has proven to deliver long term benefits with new or rebuilt engines through continued usage. Simply pour in a bottle for initial break-in, run the engine for approximately 1,000 miles, drain the system thoroughly and then refill with clean oil and another bottle of COMP Cams® Engine Break-In Oil Additive at each oil change. For more information about the COMP Cams® Engine Break-In Oil Additive or any other COMP Cams® product, call us at 1-800-999-0853, or visit us online at www.compcams.com

http://www.lucasoil.com/products/display_products.sd?iid=80&catid=3&loc=show

Lucas Engine Break-In Oil Additive - TB Zinc Plus
Key Benefits

Protects camshaft lifters and valve train during break-in period of motor.
Excellent for flat tappet camshafts during break-in or as an additive to any motor oil to prevent premature wear.
Exclusive blend of extreme pressure additives.
Add one bottle with every oil change to increase the zinc content of your motor oil.
Designed for race applications requiring additional extreme pressure additives.
Dyno testing shows a more efficient break-in when used resulting in less engine run time prior to race day.

http://www.eastwoodco.com/shopping/product/detailmain.jsp?itemID=22120&itemType=PRODUCT&iProd uctID=22120


ZDDP Plus Oil Additive

After 70+ years, the EPA mandated that all domestic oil producers remove ZDDP (Zinc Dialkyl Dithio Phosphate) from all conventional and synthetic motor oil. If your engine was designed before 1989 the non-roller lifters require ZDDP to avoid premature deterioration. ZDDP also alters bearing and journal surface characteristics to prevent metal to metal contact. Under extreme conditions like a high performance motor, ZDDP reduces the tendency of parts to scuff or gall under heavy loads. Simply add ZDDP-Plus to every 4-5 quart oil change and your motor will be protected from metal to metal contact. Add one 4 ounce bottle to a 4-5 quart oil change modifier to eliminate and metal-to-metal contact

And more are coming along every day. If you do a Google search for "zinc motor oil" you'll find that lots of people whose vehicles have flat tappets are complaining of accelerated valvetrain, especially camshaft, wear. Even though motor oils still contain zinc, the amount is being reduced, because most valvetrains today use roller lifters or roller rockers, which are a LOT easier on the valvetrain.

 

lol Here we go again

Just use your standard 10w30 10w40 quality dino oil and change it when you should and you will be fine.

the additive package in the oils nowadays are good.

dont worry

 

WE have a whole thread on this subject which seems to disagree with your viewpoint Noob. Read the data that was just posted. We need the additives b/c our engines are of an old design and depend upon those chemicals for the wear factors they provide.

 

Aloha,
I have a 1994 Cherokee SE 4D 4x4, 4.0L, AW4 which is my wife's DD. It was a police car in it's former life and doesn't have a cat.
I'm reassembling post head job, new lifters, push rods, exhaust manifold. The zddp debate got me nervous, lots of money a labor involved, so I searched the forums and grabbed some Lucas Break-in Oil.

The veteran machinist, Joel, told me to use the oil specified by Jeep, they engineered the thing. Stay away from additives.. I listen to him.

Searched again, seems zddp is a zinc, phosphorus combo and crapping out catalytic converters is the reason for reducing the levels in oil.

Jeep spec'd API SG oil for my 4.0.
SG is now obsolete, as is SL, and SJ which followed.
SM and SN are the two latest versions, and have lower levels of zinc, etc., but other friction modifiers.

Took a closer look at the Lucas Break-in Oil labels and it states DON"T use it for vehicles that require SG, SL or SJ oil.

A number of manufacturers do make oil with higher zddp levels for our older jeeps. Royal Purple HP Street, Mobil 1 15x40, and other expensive blends.
I went with Castrol GTX High Milage 10w40 which is rated at SG, SL, SJ, SM and has higher zinc juice levels or you can go with their 20w50, which is even higher, if you're going to beat on your truck.

Will also run it in my 1994 YJ, 2.5L, AX-15, Dakota bell housing, inertia ring otherwise stock mutant DD. Happily, it's on sale at Napa.

Home this helps somebody.
Big mahalo to everyone for all their help. Mike

 

been runing high mileage castrol ever since it came out never any issues

 

same here

 

I don't add zinc, just oil and filter monthly. My data is 554000 +km and rollin on. Regular service beats canned majic.

 

Now, THERRE is an informative post,! Albiet 10 years old. Will be looking into this.