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I need to replace the timing chain on my 98 Dodge Dakota 3.9L.

When looking at timing chain sets, there are about three different price points: $60, $170, $250. In the $170 and $250 sets, a needle thrust bearing is included and I assume that means the cam sprocket is already machined to accept that, i.e. I don't have to machine the block. The $60 sets do NOT include a needle thrust bearing or brass bushing.

According to this, my stock engine (which I will be keeping stock) has a roller cam. I thought with a roller cam you were supposed to use a needle thrust bearing and cam button. On O'Reilly's, there is no thrust plate listed either.

The absence of a bearing in the $60 sets has me wondering if my stock engine does not use a thrust bearing. Is there one that I'm supposed to reuse?

Do I need to purchase a timing set with a needle thrust bearing? Can this be generalized to other people?

I'm not asking about single vs double rollers.

Edit: I sprang for a nicer manual and it includes a torque specification for a thrust plate so I guess my truck has one. Does that mean using a cam sprocket without a bearing or bushing is acceptable?

Pᴀᴜʟsᴛᴇʀ2
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Zach Mierzejewski
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1 Answers1

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The thrust bearing which is listed in some of the kits is a "nice to have", but isn't needed every time. They do not normally wear out, so replacing them is probably on a case-by-case basis. I'd take a look at the old thrust plate and see if there is any galling on it. If so, then replace the plate and the needle bearings. If it looks good with minimal wear patterns (you will see some wear marks), I wouldn't worry about it too much. Replace it if you want to at this point. It definitely won't cause you any harm to change it out, regardless. If you feel it may be an issue in the future, replace it now while you have the engine apart, as it's a lot easier now then having to tear it all apart again later.

Pᴀᴜʟsᴛᴇʀ2
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