sandstone

Are the valve lifters for a '96 4.0 flat or roller?

jpdocdave

lifters are hydraulic, rockers are flat on the valves. they make an aftermarket roller rocker assembly, not worth the $400 or so bux, unless you got a lot of power in the 4.0, mainly stroker.

Howler_GT

Why? Bit noisy?

That lifter noise is factory installed.

There are several aftermarket companies that make roller rockers for the 4.0L but the cheapest is around $400-$450 (Yella Terra)

But like he said...not worth it.

Those funds could be put to far better use somewhere else on your XJ.

sandstone

No, not noisy at all. I was just wondering because I recently read that zinc is being taken out of motor oils, and it was used as an anti-wear additive, especially important in non-roller valvetrains. I started a separate thread on zinc substitutes that will help our valvetrains last longer.

kmanxj5050

yeah well i had 2 lobes wear right off my cam in my 01 about 120,000 miles, i started using Rotella oil to find out they took the zinc out too Devron or something like that has it still i will be usin that or the lucas zinc additive, Whichever is cheeper

JeepinDean

Lifters are hydraulic???? Not trying to point out an issue with this answer but I think he was asking if the lifters are roller or flat tappet.........I don't think he was asking about the rockers....

SeriousOffroad

Chevron Delo400 15w40 FTW!!

jpdocdave

the lifter is the round cylinder looking part that rides on the cam. that is hydraulic. the push rod sits in the lifter on the bottom side, and the other side of the push rod pushes against the rocker. the rocker is the part that would be roller or not. the part you see when you take the valve cover off is the rocker arm, not the lifter.

i understood the question, and answered that it is not a roller rocker. i was also pointing out the terminology without saying so. there are no roller lifters. thats all

SeriousOffroad

The answer is that the lifters in a 4.0L I6 motor are flat.

jpdocdave

ok i don't have a ton of time to put up links here, but this is an article about roller rockers. the rocker arm is what is flat or has a roller. http://www.angelfire.com/my/fan/roller_rockers.html

these are jeep lifters. they are hydraulic. they call them hydraulic cuz it uses engine oil pressure to pump up and take up any gap in the clearance.http://cgi.ebay.com/ebaymotors/JEEP-...4506.m20.l1116

stock rockers are flat, rollers are available in the aftermarket.

there is no suck thing as a roller lifter, at least not in a push rod engine.

there are engines that have solid lifters, and they require valve adjustments to maintain the valve lash clearance. these have nothing to do with jeeps, but wouldn't want that getting confused in here either

the only reason i'm putting this up is terminology is important in these discussions, and for those learning about this stuff, mis information doesn't help, even simple terminology, cuz i think we all know how it works, but the terms aren't right. if you go to the grocery store and ask for a cucumber, you might get a zuccini. thats all.

SeriousOffroad

Check your facts before posting. Yes there most certainly are roller lifters for push-rod engines.

Chevy, just as an example:


The corresponding pushrods are ball-end, not flat.

Want Roller Rockers for your 4.0? THE best out there... Harland Sharp Part# S4096

Yes there are companies offering custom Roller Lifter cams and roller lifters.
Some reading for ya.
http://www.jeepstrokers.com/forum/vi...it=roller+cams

http://www.naxja.org/forum/showthrea...ght=Roller+Cam

jpdocdave

wow, i've never seen roller lifters before. what did they come stock in?

oh crap, now that i've seen that picture i've replaced one before, one side of the roller crapped out. edit: no now that i look closer i had to replace a roller rocker in a car before.

when i'm wrong i'm wrong, i was wrong about no roller lifters.

the original question is are lifters in jeep roller, the answer is no, they are flat. i was assuming we're talking about how it rides on the valve where the rocker is. since that's the only mod i've seen for jeep valve train. i've never heard of a roller lifter for a jeep, there is roller rockers

thanks for the info on the lifter

jpdocdave

crap, i apologise on this one. just lookin at this more, and i realize that i can remember those on gm cars also, it rides on a roller against the cam. i immediately jumped to thinking we're talking about the roller rocker.

SeriousOffroad

Just about every newer model pushrod motor is running roller lifters. The majority of the manufacturers made the swap when the EPA mandated the removal/reduction of ZDDP (Zinc) from conventional motor oils because of its classification as a heavy metal.

No ZDDP = Cam/flat tappet lifter failure.

jpdocdave

this i remember, for some reason how it rides on the cam was completely out of my mind, and i was only thinking of how the rocker rides on the valve.