Rattle/Shake during normal use, Rough Idle

If the engine has a rough idle you know you have a miss-fire or other problem with one or more cylinders.
When you shift into overdrive the engine is working harder than in normal drive because of the lower torque/RPM.
So any slight miss under normal conditions will be magnified in overdrive or with the ac on.
See if you can nail down the cause for the rough idle.

Most of these transmissions cannot be adjusted for slippage. Try an Amaco transmission shop, most will diagnose, tell you what the problem is, and give you an estimate for free.

usually rough Idle is not noticable at high ildle. Once it is idles normally try Disconnecting one injector at a time. If the idle stays the same than that cylinder is the culprit. Remove that spark. If it is wet than do a compression test. Should read better than 100lbs of compression.If compression is good take a spark plug and hook it into the end of the plug wire.Lay it across the intake,start the car and watch for spark. If you have spark than you probably have a bad injector. A miss will cause the vehicle to idle high. The computer is trying to keep the car from dieing out. Hope this helps. No spark do a tune up.

If you haven't changed the plugs or had the fuel system cleaned, now would be a good time to do it. The number 1 culprit for rough idles is dirty injectors or plugs. You can try an injector cleaner in a can (or bottle) for under $10 and see if it helps, and then work from there. If there isn't any improvement then if you are able to, check the plugs for any gunky buildup and if you find a bad plug, make sure you replace them all (or have them replaced) at the same time.

These pages cover the transmissions used in Jeeps over the years. Transmissions are arranged by the most recently introduced transmissions first.
Factory Transmissions 45RFE: The 45RFE four speed automatic transmission was used in 1999 Jeep Grand Cherokees with 4.7L engines. 46RE: The 46RE four speed automatic transmission was used in 1998 Jeep Grand Cherokees with 5.9L engines.
44RE: The 44RE four speed automatic transmission was used in 1996 to 1998 Jeep Grand Cherokee's with 5.2L engines.
42RE: The 42RE four speed automatic transmission was used in 1993.3 to 1998 Jeep Grand Cherokees with 4.0L engines.
46RH: The 46RH four speed automatic transmission was used in 1993 to 1995 Jeep Grand Cherokees with 5.2L engines.
32RH: The 32RH three speed automatic transmission was used in 1992 to 1995 Wrangler with 4.0L engine and it continues to be used in 1997+ Wrangler with 4.0L engine.
30RH: The 30RH three speed automatic transmission was used in 1992 to 1995 Wrangler & 1992 to 1996 Cherokee with 2.5L engine.
AW4: The AW4 four speed automatic transmission was used in 1987 to 1990 Jeep Cherokee (XJ), & Jeep Comanche with 2.5L & 4.0L engines. The AW4 was also used in 1987 through 1992 Jeep Comanche & 1991 through 1998 Jeep Cherokee & 1993 through 1993.5 Jeep Grand Cherokee with 4.0L engines.
AX-15: The AX-15 is a medium duty 5 speed manual transmission. It was introduced in mid 1989 in YJs with the 4.2L engine and XJs and MJs with this engine. The first year of the Grand Cherokee (ZJ), the AX-15 was rare option only with the 4.0L engine. The AX-15 is still used in TJs and XJs with the 4.0L engine.
AX-5: The AX-5 (and AX-4, the non-overdrive version) is a light duty 5 speed manual transmission. It was used in all Wranglers from 1987 equipped with the 2.5L I4 engine. It was also used in Cherokees (XJ) and Comanches (MJ) with the 2.8L V6 and 2.5L I4.
BA10/5: The BA 10/5 is a light duty 5 speed manual transmission. It was used in all 4.2L equipped Wranglers (YJ) from 1987 to mid-1989, and all 4.0L Cherokees (XJ) and Comanches (MJ) for the same years.
T-5: The T-5 is a light duty 5 speed transmission used in CJs from 1982 until 1986. It was also found in some 84-85 Cherokees (XJ).
TF727: The TF 727 is a heavy duty 3 speed automatic used in full sized Jeeps (SJs and J series pickups) from 1980-1983. From 1984-1992 the 727 was only used in these trucks with the AMC 360 V8.
999: The 999 is a medium duty 3 speed automatic used in CJs from 1980-1986. It was also used in 1984-1990 SJs and J pickups with the 4.2L engine, in the YJ from 1987-1991 with the 2.5L and 4.2L engine, and in the XJ and MJ through 1986.
904,909: The 904 and 909 are light duty 3 speed automatic used in CJs from 1980-1986 only with the I4 engine. It was also used during this time period with XJs and MJs with the I4 and V6 engine. The 909 is a 904 with a lock-up torque converter.
SR-4, T-4: The SR-4 and T-4 are light duty four speed manual transmissions used in CJs from 1980 until 1986.
T-176, T-177, T-178: The T-176, T-177, and T-178 are a medium duty four speed manual transmission used in Jeep CJs, SJs, and J pickups from 1980-1986.
T-150: The T-150 is the 3 speed manual transmission that was used in CJs from 1976 to 1979.
T-18: The T-18 is a heavy duty four speed used in Jeeps from 1971 until 1981. It was only used in the CJ from 1971-1979.
T-15: The T-15 was used only in V8 equipped CJs and Jeep trucks from 1972 to 1975.
TH400: The TH 400 is a heavy duty three speed automatic that was used in CJs with the BW 13-39 transfer case from 1976-1979. The TH 400 was also used in full sized Jeeps (SJs and J series pickups) from the late 60s until 1979.
T-14: he T-14 is a three speed transmission used with the "Dauntless" Buick V6 and AMC I6 from 1967 to 1975.
T-86: The T-86 is one of the three speeds used with the many CJs and Jeepster Commandos with the "Dauntless" Buick V6.
T-98: The T-98 varies only slightly from the T-18. It was used from the 50s until 1970 in different Jeeps.
T-90: The T-90 was the standard three speed for CJ and their military counterparts built from 1945 until 1971. It was also the standard transmission for Willys Wagons, Willys Pickups, FC trucks, and Jeepster/Commandos during this time period.
T-84: The T-84 is a light duty three speed used in MBs and GPWs during WWII

Good luck!!!

around 75,000 miles, plus or minus 15,000 or so. when you say shaking, do you mean a rough idle? thats not cause by your transmission per se...

Sounds more like a weak fuel pump, idle controller, or well, theres a bunch of reasons you could have a rough idle.

Your tranny need to be repaired at once. The tranny is slipping. Some Lexus owners do have the similar problem including myself.

The egr valve is located on the front of the right cylinder head. It has a tube attached to it and going to the intake manifold.It has failed and is why your jeep is running rough and hesitating. Replace it and it will fix your driveabllity issues. Disconnect the battery for 2 min to clear the code.

has anyone checked for a vacum leak? a vacum leak will cause rough idle at idle. check the lines from the pcv valve.

check your transmission fluid,the motor will stall when fluid is low