knocking sound from bellhousing?
 

I have a 95' cherokee with a automatic. After my jeep gets up to running temp a knocking sound starts coming from the bellhousing area:brickwall:. It only makes the sound at idle speeds (brake applied or not). At first I though is was a rod bearing, but after closer listening it's definetly coming from the bell housing area. Could there actually be something wrong with the flexplate or torqueconverter that would make that sound?:dunno:.

The autos are known for loose torque converter bolts.

Easy fix, in itself.
Have to remove the inspection cover on the front of the bellhousing.

Tighten up 1 bolt.
Turn motor (usually by hand w/big screwdriver)
Tighten next bolt.
Turn motor
Tighten bolt.

Put everything back together.

IF the noise still persists, mostlikely it is not coming from bellhousing.

While engine is COLD, shake the living daylights out of the catalytic converter.
Listen for anything that remotely sounds like a rattle.

XJ's are also known for faulty catalytic converters.
The catalyst inside breaks into smaller pieces. These pieces actually look like charcoal briquettes. And can sound like maracas inside the converter housing.
This is also an easy fix....replace catalytic converter. Great if you need to replace your exhaust system.

If your bolts are loose in the torque converter use some locktite. Locktite will hold on to those bolt really well. Whenever I build an engine I always use locktite. So remove that cover plate and check your bolts. Also when your tightening them down use a torque wrench and torque the bolts to 25ft lbs if there 10mm bolts or 42ft lbs if there 12mm bolts.

Thanks for the advise...I'm hoping that's all it is. I'll give a update after I look at it this weekend.

Please do. If thats not the problem let us know so we can help figure out what else it could be.

i have a 1990 limited cherokee auto 4.0 that i got yesterday, the noise is annoying ande feared it could be worse then the flex plate.....do i have to drop the tranny in order to tighten flexplate bolts?:icon_rolleyes:

No. Just remove the inspection cover.

JeepersCreepers: Which locktite would you advise the blue or red? I think I have the same issue as well.

sean

thanks timberwolf, i did that today but that did not resolve the issue. Im pulling the tranny tomorrow to replace the flexplate and locktite everything. vancouver huh? thats where i got the jeep.:thumbup1:

Cracked flex plate....
 

Well...I know i took a long time to responed...so I apologize. I found that the Flexplate was cracked from one bolt to another, causing the flexplate to "pop" or "knock". It was an easy fix once I got the correct parts; a new flexplate from a jeep dealership and a Crankposition sensor located on the top of the bellhousing. It broke during the installation.

PLEASE READ; Do not try to use cheap off-shore parts for these jeeps....there were so many changes during the years...due to the changes of ownership of the "jeep" name. After trying a cheap replacement (made in Mexico) my jeep was running on 3 cylinders due to the position sensors located on the outer-ring of the flexplate. They did not match the original flexplate and caused the computer to receive false crank position data...which caused the jeep to run crappy. Once I installed the correct flexplate (from Jeep), two different ones for the same year, and a new crank position sensor, She ran like a dream:scooter:

How much was the flex plate from the dealership?

ok....i might sound like a idiot but how many bell housing bolts are there? Dont have a manual so trying my best. I should probably go get one. But as of right now the jeep is on ramps in the garage torn apart ready to drop the tranny, how much did the new flexplate cost from jeep? did you order it off line? Any helpful tips in order to remove and or install the new flexplate?:D

I don't remember how much the flex-plate cost at the dealership. I do remember the difference in price between the "cheap" one I ordered on-line and the one I got threw Jeep (made in canada) was maybe $10 dollars more.

When I order threw Jeep, they needed my VIN # because there were two different flex-plates available for my 95' 4.0l with the AW4 automatic tranny. The only way to get the right one was by using the VIN #.

As far as bolts for the bell housing....maybe 5....three on the top and one on each side...don't remember. Don't forget to detach the flex-plate from the torque converter...you won't be able to pull the tranny out.

redjeepster, could you give me a link or website name so i can order my flexplate from jeep? i only want to have to do this once so might as well do it right. also, has anyone used wheel spacers to gain width of the tires? read about it somewhere but not sure if it was a good idea. Did the automatic cherokees come stock with a transmission cooler?

As far as a web-site....I don't have a good one. The first flex-plate I order was threw a website called something like "auto-parts"...but that Flex-plate turned out to be completely wrong. The only reliable source I can give is to physically go to a Jeep/dodge dealership with your VIN#. If that's not possible, maybe you can call your closes dealership and order from them and have it sent to you.

As far as a transmission cooler....yes the automatic jeep comes stock with one. It's located within your Radiator. The Jeep's share the radiator to cool the engine coolant and transmission fluid. It work's fine for normal driving...however, if your plan on pulling your max gross weight for a long road trip or participate in extensive/severe of road fun....then invest in a external cooler and install it in-line with your existing cooler. If you live in a cold climate area it's best to install the external cooler inline with your stock cooler, this allows the radiator fluid to "warm up" or "transfer" heat to your transmission fluid. This is needed in colder climates. If you live in florida or something similar...then you could just us the after-market "external" cooler by it's self.