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TJ Engine Lift Page

One problem with the Jeep TJ is that suspension lifts can result in less than optimal rear driveshaft angles. Poor driveshaft angles can be one source of driveline vibration in a lifted TJ. The typical solution is to drop the transfer case using the 1" spacers provided by the lift kit manufacturer, and/or, install a transfer case tailshaft shortening kit. I have a TJ with the worst possible combination of transmission and axle. It seems that the 5 speed transmission is longer than the automatic, and the Dana 44 has a longer pinion shaft than the Dana 35. This results in the shortest driveshaft length and thus the steepest driveshaft angle when the TJ is lifted. But, even TJ's with autos and D35's can benefit from an engine lift! The reason is that if the engine is lifted it angles the transfer case output shaft downward. The axle pinion shaft needs to be parallel with the transfer case shaft so it must be tilted upwards. The result is that both shafts are now more closely aligned and the U-Joint angles of the driveshaft are reduced.

Here's some reasons I like the engine lift approach:

1. You can get rid of the transfer case spacers and get precious ground clearance.

2. Your oil pan gets another 1" of ground clearance.

3. The 1" engine lift requires that you install a 1" body lift. Body lifts would be very easy except that they require that you drop the radiator so that the fan stays lined up with the fan shroud. With the 1" engine lift you Don't have to drop the radiator!. This a real advantage if your jeep has air conditioning as body lift manufacturers don't even recommend their lifts for air conditioned TJ's because dropping the radiator is such a PITA.

4. The required 1" body lift is the cheapest inch of lift you can get. I've got the 3 1/2" Terra lift and still needed more to clear 33x12.50's without the tires hitting the fenders. The 1" body lift was the ticket.

5. The engine lift is easy to install.

6. The original engine mounts are retained. Other engine lift methods that replace the original mounts cause excessive noise and vibration in the cab, plus they cost more.

To do a 1" engine lift the following parts are needed:

1. Performance Products 1" body lift kit (you really just need the pucks and bolts and not all the parts for drpping the radiator but it's easier to order the whole kit. It costs about $70 I think.)

2. 4 engine lift spacers ( By coincidence I have a part that would work!)

3. 2 10x1.5mm metric bolts, 15mm long, or, 2 10x1.5mm studs 25mm long.(the studs are best)

4. 2 10x1.5mm metic bolts, 35mm long or so (unthreaded part must be less than 1" long).

5. Nuts and washers for above

6. Locktight

Engine Lift Instructions

1. Jack up the engine to take the weight off of the motor mounts. Use a board between the jack and oil pan as the pan will dent easily.

2. Loosen the long through bolt in the driver side mount.

3. Remove the 2 bolts and nut that hold the passenger motor mount in place. Remove the mount.

4. Modify the first motor mount by cutting off the stud to 1/2" length. To do this thread a regular 10mm nut onto the stud and then cut off the stud. Clean up the cut with a file or fine grinder. Remove the nut and it will debur the cut threads also. Install the spacer onto the stud using locktight and a pipe wrench. Hold the motor mount in a vice while the spacer is tightened. The spacer is 1" thick and the stud should not go more than 1/2" into the spacer or there will not be enough room for the bolt or stud to go in from the other side. After mounting the spacer thread the 15mm bolt into the spacer and see if it goes in far enough so that it will clamp the spacer to the frame when installed in the jeep. Use washers if needed to get a tight fit. Alternately, install the 10x1.5mm stud into the spacer with locktight.

5. Jack the engine up so that the passenger side is raised about 1" higher up than stock. Check fan shroud clearance if body hasn't been lifted yet. Loosen the shroud if neccessary.

6. Install the modified motor mount with the second spacer under the mount. The second spacer does not have a threaded hole. Use the longer metric bolt through the motor mount and second spacer. Install the 15mm bolt into the threaded spacer from the underside, or, install the original nut onto the new stud, (depending on which mounting approach you took above). Don't tighten bolts yet, just snug them down. If the short metric bolt was used, instead of the stud in the spacer, make sure you can tighten it fully without it bottoming out against the cut-off stud of the motor mount!, use flat washer as spacers if needed)

7. Remove, modify and install the other motor mount using the above proceedure.

8. Make sure everything looks OK then tighten the motor mount bolts. Again, make sure the 15mm bolt into the spacers aren't bottoming out against the stud prior to clamping the spacer tightly. (this is why a stud in the spacer is better than using the bolt)

9. Install the body lift per their instructions.

10. Adjust the pinion angle so that it's parallel with the transfer case shaft. Adjustable control arms makes this easy. If you don't have the adjustable control arms you'll need the control arm adjusters available through jeep dealerships or other suppliers. These install in the upper control arm mounting points and give you a slot and cam arrangement for making the adjustment.

Additional points:

Your shifter may bind in the rubber boot. This happens with transfer case drop spacers or body lifts. Follow body lift instructions for correcting this. (I removed the shifter and bent it into a better shape. This is the best solution and the instructions with the Performance Accessories lift tells you how to do it.)

Don't lift the motor without lifting the body as the fan may hit the shroud. Check all clearances before starting the engine!!!

Please note that, as with any modification of your Jeep there will be changes in handling. This is true with any modification that changes the center of gravity of the vehicle. While changing the height of your engine is minor when compared to lifting the suspension it may still affect the handling. The instructions and comments provided here are for informational purposes only and any modifications made using this information are at your own risk. Also, as with any vehicle modification, there are differences between vehicles that may require appropriate adjustments in the installation. Guess who's responsible for this?...YOU ARE. If you don't know which end of the screw driver goes into the screw you probably need to have an experienced person help you with your work. (I hope this didn't scare you away!)