did the valve cover change in 93?

My 91 has leaks under the valve cover and oil fill cap due to the rough texture of the stock cover, so I want to replace the thing with a new smooth aluminum cover. Looking around the net however it seems that the aftermarket covers are only for 93 up. Did the 4.0 HO change in 93?

ehall said:

My 91 has leaks under the valve cover and oil fill cap due to the rough texture of the stock cover, so I want to replace the thing with a new smooth aluminum cover. Looking around the net however it seems that the aftermarket covers are only for 93 up. Did the 4.0 HO change in 93?

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They basically used four valve covers on 4.0 litres...
1987-1990-cast aluminum, had small holes for the CCV fittings-worst design IMO.
1991-1992-cast aluminum, had CCV fittings that had to be rotated 90*
1993-1995-cast aluminum, had large CCV fitting holes with full 90* bends in the elbows. *Best cast design.*
1996-2006(?)-stamped steel valve cover, retained same CCV fittings as the 93-95 style. Also had a ratcheting oil fill cap.*My favorite*

Your question of the aftermarket valve covers. They should fit any year 4.0. The one difference is that they use a composite gasket that is very similar to the 1996+ steel valve cover's. In I believe starting in 96, they used studs in the head instead of bolts by the rocker arms to center the composite rubber/steel gasket. As long as you can get the gasket square and flush on the older 95- 4.0s, you should theoretically be able to use any 4.0 valve cover including the aftermarket ones. One thing I forgot to add...the aftermarket ones seem to have a pressure fit oil fill plug that people on here have had trouble with. I'm sure someone else will chime in, but just thought I'd forewarn you.

You sir are a scholar and a gentleman

ehall said:

You sir are a scholar and a gentleman

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Hahah well sometimes and in some things...you hit on something that I spent a long time researching and trying to figure out what worked best. Let me know if you have any other questions and good luck!
-Collin

My '92 has the cast valve cover, but also has what appears to be a silicone bead permanently attached, as a gasket. A few years ago, I purchased a cork gasket before I removed the valve cover to tighten the rockers, but I've never needed to use it. I wonder if it will be of use on my '96.

I just double-checked and the CCV and whatever else is on the cover are at 90* angle already. I guess I can reuse those in a newer cover maybe.

makeitmopar.com has the 96+ OEM valve cover for like $80 so that's a good option. Actually that's cheaper than most people sell the aftermarket covers for, and it probably looks better too.

I picked up a $3 oil cap from autozone a little while ago and that seems to have stopped the leaking. I think the rubber seal on the old one was cracked.

the cork gasket sucks, you know what, spend the bucks for the rubber one with the steel inserts.

ehall said:

I just double-checked and the CCV and whatever else is on the cover are at 90* angle already. I guess I can reuse those in a newer cover maybe.

makeitmopar.com has the 96+ OEM valve cover for like $80 so that's a good option. Actually that's cheaper than most people sell the aftermarket covers for, and it probably looks better too.

I picked up a $3 oil cap from autozone a little while ago and that seems to have stopped the leaking. I think the rubber seal on the old one was cracked.

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I just remembered I have pretty good pictures of 3/4 of them. I'm judging from what you said about the seal, you must have an older 87-90 style on your 91. Not unheard of, just uncommon. If that is the case you definitely will not be able to reuse the CCV fittings, but trust me, you don't want to anyway. Anyway, to the pictures...

Here is the 87-90



The 91-92 I don't have a very good picture of, this is the only one I could find on eBay. The main difference is the CCV fittings you have to turn 45* to lock in place. It also has the bigger oil fill cap than the 87-90 does.



93-95



96+



I also just found an aftermarket one on eBay for like $70 shipped, but it doesn't inlcude the grommets, gasket, or cap.
http://cgi.ebay.com/ebaymotors/BLAC...020QQitemZ300191196329QQrdZ1QQsspagenameZWDVW

Hope this helps you out.
-Collin

ia green96 said:

the cork gasket sucks, you know what, spend the bucks for the rubber one with the steel inserts.

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x2, i used a cork one on my 89 and it leaks pretty bad. i will be using the fel-pro rubber/metal in the near future.

edit mine is the same as the one in the 91-92 picture.



The original cap looked like the one in your pic too (I replaced it yesterday due to leak)

It looks like the 96+ OEM cover would work fine but I will need to get the whole thing including fittings and brackets

ehall said:

edit mine is the same as the one in the 91-92 picture.

The original cap looked like the one in your pic too (I replaced it yesterday due to leak)

It looks like the 96+ OEM cover would work fine but I will need to get the whole thing including fittings and brackets

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Yup, just get the whole shebang, you'll be all set.