Oil Filter Conversions
Different Options: '87 through '01 XJ (4.0L)

by Andreas Ritterbusch
Posted: August 23, 2001
Last Revision: August 14, 2002

Upgrading to a larger oil filter on a Cherokee or Comanche ('87 or newer 4.0L) has been a popular option for quite some time now, and nothing is really new here...

The larger oil filter upgrade requires a change from the "metric" to "standard" filter thread. The nice thing about the standard filters is that they are also more common, especially in large discount type of stores.

Most of this article is dealing with the "non-HO" inline-6 engine (4.0L), but the article below also includes the newer 4.0L (High-Output) engine. This article does not discuss the inline-4, or the early V6 engines.

Upgrading to a larger oil filter has several advantages, as already mentioned. First of all, a larger oil filter is simply a good idea because it adds a little more engine oil to the system and, more importantly, it adds more filtering capacity. There is nothing wrong with the OEM set-up. The OEM oil filters used on Jeep Cherokees/Comanches are probably more than sufficient. A larger oil filter may allow for more tolerance between oil changes, especially if used in conjunction with a high-quality (perhaps synthetic) engine oil.

The following write-up deals primarily with the earlier non-HO engines ('87 to '90) who had the metric oil filter mounted vertically. Jeep later decided to mount the oil filter horizontally (and switching to the SAE thread). If your Jeep is a newer one, all you need is to purchase the bigger oil filter and install it the next time you do a oil/filter change. Also, I am not exactly sure when Jeep did the vertical-to-horizontal oil filter ('92/'93?).

This article does discuss the various possibilities of upgrading from metric to standard type filters, changing filter positions from vertical to horizontal, and also upgrading to a larger (non-OEM specified) capacity oil filter.

This article does not discuss the various grades of oil, the use of synthetic oils over non-synthetics, one oil manufacturer over another, or any particular brand of oil filters .

Engine oil and oil filters shown in the below images are examples only!

Definitions:

"metric", "metric filter" M20x1.5 (non-HO)
"standard", "standard filter", "SAE", "SAE filter" SAE 3/4x16 (HO)
"HO" High-Output 4.0L engine ('91 and up)
"non-HO" 4.0L engine ('87 to '90)

 
The Parts:

Here a comparison. (In the following article many references are made to "204 style", "207 style", and "301 style" oil filters.) 

From left to right:.
Left: SAE threaded,large filter, such asMobil1 "M1-301": The larger oil filter (for mid-80s Ford 5.0L engines such as the F-150 p/u).
This is not an OEM specified filter, but fits perfectly. However, the longer size of this filter can shorten the starter solenoid when removing it. Therefore always DISCONNECT the battery before removing the oil filter!
Center:SAE threaded, regular filter, such as Mobil1 "M1-204": Used in XJs with the HO engine.
Right: Metric threaded, regular filter, such as Mobil1 "M1-207": Used in XJs from '87 to '90.

Of course, you will need engine oil!From left to right:.
Left: Mobil1 5W-30 ("cold ambient temperatures")
Center: Mobil1 10W-30 ("most ambient temperatures")
Right: Mobil1 15W-50 ("hot ambient temperatures")
According to my '89 Factory Service Manual, all three SAE grades shown here are alright to use (depending on ambient temperature, of course.) Do your own research on what constitutes "cold temperatures", "most (or typical) temperatures", and "hot" temperatures" for your particular situation.

This is just an example of some left-over oil I had sitting in my shelves. It is a coincident that I had a "set" of Mobil1 synthetics.
(And no, Mobil1 is not a sponsor of MADXJ!)

Here are the parts I bought from my friendly Jeep dealer... (Part numbers are included below)

A: "Adapter" (53020080)
B: "E-bolt" (53020237)
C: O-ring kit (4720363)
D: "E-connector" (53007563)
[Large image]

Detail view of the adapter (I will call it L-adapter ). This adapter will move the position of the oil filter from vertical to horizontal in the earlier XJs ('87 to '90, possibly even later ones too).
[Large image]

Detail view of the so-called "E-connector". This connector changes the oil filter thread ("old" M20x1.5 to "new" SAE3/4x16). This connector can be used to replace the old metric connector on the earlier 4.0L engines ('87 to '90 only). The filter thread is changed from metric to SAE, but the oil filter will remain in its vertical position. Later (newer) XJs/MJs are equipped with the filters in the horizontal position.
[Large image]

Detail view of the O-ring kit. Make sure the dealer gave you the right one. Even if you decide not to go to the horizontal relocation of the oil filter, it is usually a good idea to replace the O-rings. If you keep your original setup, you will have to check with the dealer for the correct O-ring kit, which will have a different part number depending on which L-adapter you decide to use (or to keep).
[Large image]

Detail view of the "E-bolt". Unfortunately, this is a giant Torx bolt that you will introduce to your system. In addition, it is in a tight spot later on to tighten it. Make sure you have Torx T60 socket in your tool collection. Read on...
[Large image]
The Tools:

No special tools are required, except perhaps for the Torx T-60, if you consider that a special tool. Otherwise, a typical tool collection will suffice as well as your typical oil and oil filter changing equipment.
The vice grip is holding the T-60 socket since there is not enough room between the bolt and the uni-frame (see below for details).
The Procedure:

There is not much to the procedure either. Drain the oil, remove the filter. It depends if you are installing the L-adapter or not. If not, all you have to do is to remove the filter connector and replace it with the new connector to upgrade to the metric filter thread. If you do want to use the new style L-adapter, then you have to remove the old adapter and install the new adapter together with the new filter connector and all the new O-rings.
[Large image]

This blurred image shows the engine block with the L-adapter removed (looking at it from below). Be careful not to damage the little tube (green arrow).

This image shows the engine block with the L-adapter removed (looking at it from above). Be careful not to damage the little tube (red arrow).

Install the new L-adapter (if you decided to go that route) and notice how tight it gets here! The T-60 just barely clears the uni-frame rail (red arrow). I used a vice grip and set it as tight as I could and turned the Torx bolt until the vice grip slipped. The side effect of this is that I did not over-torque it. Remember, there is a O-ring behind that L-adapter. If tightened too much the O-ring gets squeezed too hard and may leak prematurely.

Install the new oil filter (view from above, here the larger "301" type filter is shown on a non-HO engine).

Install the new oil filter (view from below). Notice the big Torx bolt in this image.

Fill in fresh engine oil (and don't forget to put the oil drain plug back in first!)

You will need a little more than the six quarts of engine oil with the bigger oil filter. But that is exactly one of the advantages of this upgrade: more  filtration and a bit more engine oil.

Done!

I am using here some heavy engine oil because this engine here is old and worn and this oil helped it a bit with the oil pressure, plus, 100+ F days are not uncommon around here during the summer months.
Further Observations:

The following pictures will compare and contrast the new and old style L-adapters. I personally think that you do not need the new L-adapter. Read on...

On the left: the new L-adapter.
On the right: the old L-adapter.

On the left: the old adapter with a metric "207" oil filter.
On the right: the new adapter with a large SAE "301" oil filter.

Looking at the filter side of the adapter, notice
a) the machined (and wider) surface for the oil filter seal,
b) the larger oil passage.
On the left adapter (the new one) you can actually see the bolt. On the right side (old adapter) the oil passage is smaller (click the "Large image"in the next image for details).

On the left: the new adapter.
On the right: the old adapter.
[Large image]

This is the same image as above, but a bit brighter to show the two different oil passages. Even though the old adapter appears to have an oil passage similar in size as the new one, the picture doesn't show it all. If you have already viewed the detail image, you may have noticed the outlined areas that I put in the image to show the true sizes of the oil passages. The difference is quite obvious.
[Large image]

Now here is the interesting part! Carefully compare both, the new (right) and old (left) oil filter adapters. the red circles in the image show a little detail that I noticed when I changed the adapters
A2 is the little circular depression for the little tube shown in one of the above images. There is no groove leading from the circular depression to the center.
Now look at A1 and notice that 90 degrees from the circular depression (A2), there is a elongated depression (also without a connection to the center). At the same location, you will find a similar elongated depression on the new L-adapter (B1).
Judging by the similarities of these elongated grooves, it seems like the newer style L-adapter (oil filter adapter) is not really needed to place the oilfilter in a horizontal position! I actually tested that and all that is needed is to loosen the bolt enough for the little pipe to clear, rotate the adapter 90 degrees (towards the firewall) and re-tighten the adapter (a new seal would probably be a good idea, though, in which case the adapter has to come off all the way).
[Large image]

One more comparison revealed a slight difference in the bolts that hold the L-adapter to the engine block. The new (Torx) bolt has two large openings for the oil to pass through, whereas the original has four smaller ones.
[Large image]

Summary:

  • For '84 to '86 four cylinder/V6 XJs/MJs: No recommendations.
  • For '87 to '01 four cylinder XJs/(MJs): No recommendations.
  • For '87 to '90 inline-6 ("non-HO") XJs/MJs: There are several options:
    1. Rotate the L-adapter 90 degrees and use the original metric("207" style) filter.
    2. Replace the oil filter connector bolt ("E-connector") and use either
      1. the regular SAE ("204" style) using the original L-adapter in either
        1. vertical position,
        2. rotated/horizontal position, or use
      2. the larger SAE ("301" style) oil filter in either
        1. vertical position,
        2. rotated/horizontal position.
    3. Replace the L-adapter and "E-connector" to the newer setup and use either
      1. the regular SAE ("204" style) or
      2. the larger SAE ("301" style) oil filter.
  • For '91 to '01 inline-6 ("HO") XJs/'91 and '92:
    • Simply use the larger ("301" style) oil filter. (If yours is an early '90s XJ/MJ with the filter in the vertical/upright position, look at the '87 to '90 section for suggestions.)

 

Maybe I missed a combination or two, but that is not all that important. Hopefully the article demonstrated the various possiblilites and will aid in the decission making process.

I myself are using the larger "301" type oil filters in both my XJs ('89 and '97). The biggest motivator for me was to have both vehicles with the same oil filter thread (now both SAE), so I don't have to keep track of different spare filters, etc. This allows me to use either the OEM specified "204", or the large non-specified "301" oil filter in either the '89 or the '97 XJ.

Most of the time I confused the filters and tended to end up with the wrong filter while being in the middle of a oil/filter change. (No more "Oh sh%^! --Not again!!" moments.)
©Copyright 2001 Andreas Ritterbusch
All Rights reserved.
Photos: Andreas Ritterbusch

 

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