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Swapping a Ford T-18 into your CJ may be the best alternative, because in many cases it can be swapped in cheaper and easier than any other transmission. The improvement in performance and durability of your CJ will increase exponentially with this relatively simple transmission swap. Ford T-18s are easy to find and inexpensive to buy and the Ford T-18 is compatible to a large degree with '76-'86 CJs because in most cases the originally bell housing can be retained.

A Jeeping buddy of mine, Steve Smith, asked me to help him swap in a Ford T-18 in his '83 CJ-7 since I put one in my CJ-7 a couple of years ago. I figured it would be an excellent opportunity to document the swap, so I foolishly agreed. Just about everything that could go wrong, went wrong during this swap, but the end results were well worth it.

Steve's CJ-7 was originally equipped with a 258, T-176, and Dana 300, but the previous owner "upgraded" to a T-5. Steve is mainly interested in rock crawling and although the T-5 had served him well so far, he knew it wouldn't last long. He wanted a heavy duty transmission with a granny first and the Ford T-18 was the least expensive option.

 

 

Table of contents

1 The Search   2 The Rebuild   3 Clutch and Pilot Bushing   4 Bell Housing   5 Skid Plate and Transmission Mount   6 Drive Shafts   7 Shift Lever   8 Transfer Case Linkage   9 Breather   10 Electrical   11 Weight   12 Converted Ford T-18   13 Conclusion   14 Contributors

 

The Search

A local guy that does bench rebuilds in town recommended that Steve find a good runner over a core even though the transmission would need to be rebuilt. The thinking is that if any major parts are damaged in a core, the cost of new parts will far exceed the cost of a good runner. Steve purchased a running T-18, but the shift lever was missing. It seems that the shift levers and the input bearing retainers are some of the most commonly damaged parts on Ford T-18s and this one was slightly cannibalized.

Ford T-18 with adapter next to a T-5

Most Ford T-18 conversion kits I've seen replace the main shaft and the tail housing of the transmission, so when you searching for a Ford T-18 to swap into a CJ with a Dana 300, it is best to get the 2WD version. The 2WD versions are generally cheaper than the 4WD versions and the adapter kit bolts right on the 2WD version where the 4WD version may need to have holes tapped in the case.

 

The Rebuild

Steve dropped off his Ford T-18 and a conversion kit from Advanced Adapters at a for a bench rebuild. Bench rebuilds are fairly inexpensive, normally $150-$200 plus parts. New bearings were put in this transmission and a synchro was replaced. It is well worth to replace any questionable parts at this time.

 

Clutch and Pilot Bushing

Advanced Adapters makes a special pilot bushing for the conversion that is AMC on the outside and Ford on the inside. It is not part of the Ford T-18 conversion kit, so you will need to order it separtely. You can make you own pilot bushing by taking a stardard Ford pilot bushing and turning down the outside to the size of the outer large hole in the crank shaft. I've had one custom made at a clutch shop local, but there was no cost savings over the Advanced Adapters bushing.

A standard pressure plate can be used for the conversion, you may want to keep your old one if it is fairly new. Since pulling a transmission is very time consuming, a new pressure plate is a good idea if you haven't put in a new one in a while.

The Jeep T-150, T-18, T-176, SR-4, T-4, and T-5 all use a 1 1/8" 10 spline input shaft and the Ford T-18 uses a 1 1/16" 10 spline input shaft. Your old clutch disk will not fit snuggly on the Ford input shaft, so you will need to purchase a new disk. The disk can be a regular 10 1/2" Ford disk (or 11" if you have an 11" clutch). The Centerforce clutch disk #384180 is a 10 1/2" clutch that will fit the Ford transmission.

 

Bell Housing

The bell housing bolt pattern for the Ford T-18 is exactly the same as the T-150 and the T-176 transmissions. The Jeep T-18 has one bolt hole different, the bolt near the clutch fork is higher on the Jeep version. The SR-4, T-4, and T-5 use a different bolt pattern.

Steve's Jeep had the bell housing that went with the T-5, so the holes didn't line up quite right. If you drill carefully, a drill press would help here, you can drill out the bolt pattern for the Ford T-18 on one of these bell housings. The transmission can be tilted a bit to the left or right, alignment on that plane is not critical. We were trying to drill out the holes with a hand drill and messed up one of the holes, so Steve purchased a used bell housing for $30 with the proper bolt pattern. If you are going to drill the holes, make sure you have the right size bit for the tap you are going to use to thread them.

 

 

Skid Plate and Transmission Mount

 

Minor modifications are required to the skid plate to fit the larger T-18. A notch needs to be cut in the leading edge of the skid plate to allow room for the drain plug in the bottom of the T-18. The picture on the left shows the modified skid plate with notch cut out. The notch was cut with a regular circular hand saw with metal cutting blade.

 

On the transmission mount, Advanced Adapters supplies a aluminum spacer block to mate the bolt holes in the bottom of the transmission to transfer case adapter to the transmission mount. This spacer block forces the transmission very close to the tub and causes a minor drive shaft vibration with a 2 1/2" spring lift. Dropping the skid plate would resolve the problem, but at the cost of ground clearance.

In order to set up the transmission mount with out losing ground clearance, the transmission mount must be modified. It is easier to take care of this before you install the transmission.

 

• Toss the spacer block in your scrap metal pile.
• Bolt the torque arm directly to the transmission to transfer case adapter directly with the bolt hole on the drivers side (fig. 1, item D) and the limiting donut to the drivers side.
• Mark and drill the torque arm for the other hole (fig. 1, item B) into the transmission to transfer case adapter. Bolt the torque arm with both bolts to the transmission to transfer case adapter.
• Drill and tap the transmission to transfer case adapter for the hole in the torque arm that falls between the two holes (fig. 1, item C) that bolt into the adapter. This hole should be either for a 1/2" or 7/16" bolt. The transmission mount will bolt through the torque arm into the transfer case adapter.
• Cut a small notch out of the middle of the transmission mount with a circular hand saw (fig 1, item E). The notch needs to be large enough for the head of the bolt.
• The passenget side bolt hole for the transmission mount remains unchanged (fig. 1, item A).

Drive Shafts

If you are swapping in a Ford T-18 for a T-176 or T-150, the rear drive shaft may need to be shortened and the front drive shaft may need to be lengthed since the overall length of the Ford T-18 and adapter is longer than the T-176. If you have an SR-4, T-4, or T-5, no drive shaft modifications are required for the swap if you use the Advanced Adapters kit.

 

Shift Lever

The shift lever for the Ford T-18 is in the same place as the shift lever for the T-176 and T-150, but is several inches forward of the shift lever for the T-5, T-4, and SR-4. For these transmissions, a hole must be cut in the tunnel cover for the T-18 shift lever and the old hole should be covered with sheet metal. If you have carpeting over the tunnel, you'll end up with an extra hole in that as well. A new boot is necessary, especially if you have the integrated transmission and transfer case boot.

Depending on the source of you Ford T-18, you might need to heat and bend the shift lever so it clears your console and dash. The T-18 in Steve's Jeep is from a '83 Ford pickup and it did not need any bending. My Ford T-18 is also out of an '82 F-250 and the lever is snug on console. I've had my T-18 pop out of reverse a couple of times when there is a lot of flex, but it normally doesn't happen.

 

Transfer Case Linkage

If you have a T-5, T-4, or SR-4, the position of the transfer case is nearly unchanged. No modifications are necessary to the transfer case linkage or the hole in the tunnel cover. Modifications may be necessary to the tunnel cover when you are swapping out a T-176 or T-150 because the transfer case lever will be repositioned slightly.

 

Breather

Most Ford T-18s I've seen come with a little pop-up breather. While the transmission on the floor, it would be a good time to remove the pop-up breather, remove the transmission top cover, and thread the hole with a tap. A short barbed fitting can be installed to run a long breather hose somewhere high. The hose can be tied into the transfer case breather if your original transmission didn't have a breather hose.

 

Electrical

The easiest thing to do with the backup switch is cut the other end of the plug out of the donor and splice it in. There aren't many styles of backup switch, so your old plug may work with the Ford T-18. The switch from you old transmission might even work in the Ford T-18. None of those options worked for me, so I spliced in a 2 wire plug and put soldered the wires to the Ford T-18 switch. After soldering the wires on the switch, I filled it with RTV to keep it water proof.

 

Weight

You'll find a significant difference between the weight of the Ford T-18 and your originally tranmission. The transmissions used in 80s Jeeps all have aluminum cases and weigh about 80 pounds or so. The Ford T-18 weighs closer to 150 pounds dry. A good transmission jack will help a great deal for installation.

 

Converted Ford T-18

 

 

 

Conclusion

Most of the problems with Steve's Ford T-18 swap were not directly related to the swap itself. One big problem we had was Steve didn't have a shift lever right off. This wasn't really much of a problem, but we hadn't run the transmission through the gears until we had it completely installed. It turned out one of the dogs popped off somewhere along the way and we had to pull the entire thing and take it back to the transmission guy. Shift your transmission through the gears before you install it! The other problem we had was Steve chunked a rear bearing on the test drive, completely unrelated, but it meant Steves Jeep sat in my garage for an extra week or so.

The payoff in the end was big. The truck crawls much better and it doesn't leak trans fluid on steep climbs like the T-5 tends to. Steves crawl ratio went from 3.31*2.62*4.03 = 34.94:1 to 3.31*2.62*6.32 = 54.79:1. Reliability of the transmission is also greatly improved with the heavy cast iron case and larger gears.

 

Contributors

Thanks to Jeepin Joe Heinrich for the 2WD Ford T-18 picture. Thanks to Predator 4 Wheel Drive for allowing some of the converted Ford T-18 pictures.