1999 Jeep Grand Cherokee vibration and whining/humming noise

DOES IT DO IT IN PARK AND ON THE GAS PEDAL?

THE MEDIC

Nope this sound only occurs while driving down the road. The sound becomes audible at 35-40+ mph but that could be because of the sound of the Flowmaster overpowing it at lower speeds :). This sound only occurs while my foot is on the gas. I have checked the exhaust for anything rubbing or leaks and i found nothing. After three hours of driving above 55 mph this weekend Im preaty sure the sound and vibration is occurring somewhere in the front differential or front driveshaft or possibly transfer case or transmission. I can tell there is a little sound and vibration at the lower speeds but it's way to faint to locate below 35 mph. I do allot of driving above 55 mph in the summer as I go to Appomattox so this needs to be fixed before it drives me nuts!

I did look under it again and I found a slight problem with the driveshaft. I will try uploading some pictures.

I'M NOT UP ON THE CHEROKEE DRIVETRAINS OVER THE YEARS

WHAT SYSTEM DO YOU HAVE?.....TRANSFER CASE?

IF THIS IS PUSH BUTTON 4X4---IT MIGHT BE THAT SOMETHING DID NOT DISENGAGE....LIKE A FRONT HUB

'NUTHER POSSIBILITY

THIS IS OFTEN OVERLOOKED

...........WELL THEY GET "LOOKED AT", BUT PROPER INSPECTION IS NOT DONE......I WILL REMAKE THESE PICS ONE DAY, I MADE THESE WHEN I WAS STILL SORTA "GREEN" ON THE COMPUTER, MY COLOR CHOICES LACKED........THESE ARE ON MY '46 WILLYS.....YOURS ARE VERY SIMILAR

RETURN WITH A GRIN!

ARE YOU ABLE TO MAKE REPAIRS YOURSELF....I GOT MORE INFO SHOULD YOU NEED TO REPLACE THEM

THE MEDIC

Nice jeep! Okay so I have checked the drive shafts for any play and I found none. I did get some pictures to show some possible causing things and I will put those on shortly. My system is a quadra trac two and it has a 247 J transfer case

Okay I could only get those two pictures to cooperate with me but they show my main two concerns. The first picture is showing my front driveshaft where it enters the transfer case and the rubber or whatever it is is cracked and opened almost half way around. My second concern is shown in the last picture with the rear driveshaft from the transfer case to the first u joint it almost appears to me like the driveshaft is being pulled out. I saw this at first two days ago and when I went back to look at it just now it appears as if it has come out more. These are not all of my concerns but certainly these two things appear like they could be a problem.

One correction, the transfer case is a NEW PROCESS GEAR 247 J

As for repairs...... Yes me and my dad can do the repairs but I think if its gonna cost more than $500 then ill just sell it for somone else to do all the fun work. I've had it for only a year and I love the abilities of the quadra trac 2 system and the awesome fuel economy but with the brake problems in the past and other little things that need to be replaced, I'd rather sell the jeep and put down the extra $1000 this one is gonna need for repairs towards a nice truck.

THE TRANSFER CASE/ DRIVE SHAFT MAY BE NORMAL.......AS YOU HIT BUMPS, ETC, THE REAR SUSPENSION MOVES, THE DRIVE SHAFT IS PULLED IN AND OUT OF THE TRANSFER CASE ON SPLINES.

DEPENDING ON HOW YOU STOPPED IN FORWARD OR REVERSE AND HOW FAST, EVEN TERRAIN, MAY "TORQUE" THE REAR END UP OR DOWN......THIS MAY ACCOUNT FOR YOU SEEING A DIFFERENCE IN THE SHINY PORTION'S LENGTH STICKING OUT OF THE TRANSFER CASE

CAN A PASSENGER "HANG OUT" OF THE WINDOW AND LISTEN TO YOUR FRONT END???

THE DAMAGED CV BOOT IN YOUR PIC, "COULD BE" YOUR RACKET. THE BOOT KEEPS TRASH AND DIRT OUT OF THE BEARINGS. IF YOU'VE BEEN 'MUDDIN', YOU MAY HAVE ACCELERATED THE BEARING'S WEAR AND ABILITY TO WORK CORRECTLY.

A NEW CV JOINT MIGHT BE IN ORDER.........WHEREVER YOU LIVE.........DO YOU HAVE AN "ADVANCE AUTO PARTS" STORE NEARBY???

NEVER "SETTLE" FOR ANOTHER TROUBLE MAKER VEHICLE........IF THE WINDSHIELD WILL NOT LAY DOWN.....YOU DON'T WANT IT!

THE MEDIC

I SORTA TOOK OLE TUCKER IN UNDER MY WING, HE'S IN COLLEGE, LOVES HIS JEEP, NEEDED TO LEARN HOW TO WORK ON HIS NEWLY PURCHASED JEEP.....MAINLY, CATCH UP ON NEGLECTED MAINTENANCE.....WE MESS W/ HIS ABOUT ONCE A WEEK

.......SO, I DROPPED THE WINDSHIELD THEN I LET TUCKER DRIVE WILLY, MY '46, WHILE WE TOOK A BREAK FROM WORKING ON HIS '81 CJ 5 (HIS IS LEFT OF "WILLY" IN 1ST PIC)

.......................HE IS NOW HOOKED!.....WANTS A WILLYS TOO!!!!!

THE MEDIC

Okay so the vibration and sound getting worse when I hit bumps and at the top of hills makes me think that as those things are happening , the driveshaft being pulled in and out of the transfer case is making the sound perhaps something gets mis aligned? Also there is a leak in my front which In my pictures shows that it looks like its coming from a tube in the engine bay that runs down and it is just resting on my differential. This has been leaking for months and I did get a picture of where the tube is coming from.

YOUR LAST PIC KINDA GOT ME LOST, I COULD NOT MAKE MUCH OUT OF IT

EVER HEARD OF "THE DEATH WOBBLE"???

MAYBE THIS IS THE EARLY STAGES?.........SEE WHAT THIS FELLER SAYS

'ROUND HERE, WE HAVE WHAT I CALL "ALIGNMENT SHOPS" .............AND WHAT I CALL "AN ALIGNMENT SHOP"

THE 1ST DABBLES IN EVERYTHING, ALIGNMENTS ARE SORTA AN "ELECTIVE" THEY MAY GO A WEEK BEFORE THEY DO ONE.....MANY TIMES, THE "HELP" IS INEXPERIENCED.

"THE ALIGNMENT SHOP" SPECIALISES IN ALIGNMENTS AND SUSPENSION....CARS TO BIG TRUCKS!

.........................THIS IS WHERE I GO!!!

FIND YOU A DUMP TRUCK/ CONCRETE TRUCK/ ETC. OPERATION AND ASK THEM WHERE THEY GO!

AGAIN, 'ROUND HERE, THE FELLERS AT "THE ALIGNMENT SHOP" WILL COME OUT AND SORTA GIVE YOU A "QUICK VISUAL AND QUICK HANDS ON" DIAGNOSIS.......REMEMBER, THEY CAN'T SEE SOME OF THIS STUFF TILL THEY "GET IN"

NEVER-THE-LESS........FROM "EXPERIENCE" THEY WILL MOST LIKELY BE ABLE TO TELL YOU WHAT KINDA STUFF MIGHT BE FOUND DURING EXPLORATORY SURGERY........EVEN MIGHT BE ABLE TO GIVE YOU A "BALL PARK ESTIMATE"

IF YOU FIND YOURSELF UNABLE TO LOCATE THE PROBLEM.......I'D GO THE "THE ALIGNMENT SHOP".......THIS MIGHT BE A FREE DIAGNOSES (EXPERIENCE AND REAL TIME).......YOU MIGHT THEN DIY OR LET THEM FINISH THE JOB

WHATCHU THINK?

THE MEDIC

My last picture is pointing towards the front of the vehicle showing the front differential and a tube coming down from the driver side of the engine bay. i believe this is the overflow for the differential but lately it has been leaking quite a bit and so i am going to check the differential fluids as we fix the cv boot. Im just confused why this tube is freely resting on the differential and is leaking so much.

THIS COULD BE THE "VENT" FOR THE DIFFERENTIAL

ON CJs,THE HIGH END OF THE HOSE HAS EITHER A METAL OR PLASTIC FITTING.

THE VERY END OF THAT HAS A "SOMEWHAT" FLOPPY CAP THAT ALLOWS AIR IN AND OUT, AND KEEPS THE MAJORITY OF DIRT OUT

HENCE....THE REASON IT'S UP HIGH WHERE "REASONABLE FOLKS" NEVER WILL BURY OR SUBMERGE IT......THE OTHER DIFF PROBABLY HAS ONE TOO

WILD GUESSING....MAYBE YOUR DIFFS ARE OVERFILLED?

NOT BEING REAL UP ON CHEROKEES, MY BUDDY HAS A 1987 WRANGLER (YJ) THERE ARE 3 VACUUM LINES THAT GO TO THE FRONT AXLE THAT ENGAGE OR DISENGAGE THE AXLE (NOT THE DIFF) ........I DON'T THINK YOU ARE REFERRING TO THAT

I WILL HAVE YOU SOME REALLY GOOD INFO---AFTER YOUR NEXT RESPONSE........I WORK UNTIL ABOUT 2030 HRS THIS EVENING, AND WILL GET BACK ON SOON AFTER

THE MEDIC

Yes this line does have a white/ clear plastic end but no cap and from my research i think it is supposed to be mounted up high where no water can get in not just laying on my differential. In the group of pictures I posted at first there are two pictures that are identicle and they show where that tube is coming from. It's the black tube that is connected to somthing below the brake lines and other brake stuff in the middle of the picture.

Well this afternoon I decided to put a camcorder in the engine bay and drive down the road. When I listened to the recording I could not hear the sound so I do not think it is the air box. Also I checked the fluid in the front differential and it is perfect and I fixed the tube after looking at the differential I discovered that the plastic end went into the top of the differential as a breather tube as you said.

OK........I REALLY HATE GIVING UP THE FOLLOWING INFO

KINDA TAKES AWAY THE NEED FOR ME!

THIS INFO IS THE BEST YOU CAN EVER GET FOR YOUR JEEP.....IT IS "WELL EXPLAINED"...TESTING AND TROUBLESHOOTING....ETC...ETC

IT MAY BE A BIT HARDER TO NAVIGATE THAN A BOOK (THIS IS ACTUALLY "THE BOOKs" SCANNED ONTO A SITE)........I RECKON I'M OLD FASHIONED AND LIKE TO FLIP PAGES....DOG-EAR PAGES....USE MY HIGHLIGHTER TO MAKE THINGS SORTA STAND OUT

BEST THING TO DO IS JUST SIT DOWN GO THRU/ SCROLL THRU EVERY SECTION FOR YOUR PARTICULAR VEHICLE QUICKLY....JUST TO GET A FEEL OF ALL OF THE INFO IN THERE-----------THEN GO BACK AND FIND SPECIFIC INFO YOU DESIRE!

https://www.2carpros.com/questions/2005-jeep-tj-4-cylinder-6-speed-2-5l-wrangler-need-change-transmission-fluid

THE LINK ABOVE CONTAINS ALL YOU MIGHT EVER NEED........THAT IS ......"STOCK STUFF"

CONTINUE TO LEMME KNOW YOUR DEAL AS YOU GO..........I KNOW YOU WON'T NEED ME MUCH LONGER!...............EVEN THE QUESTION ASKER IN THE LINK...NEVER CAME BACK!

THE MEDIC

Did not get a chance to look on the website yet but today I put a camcorder directly below the transfer case and drove down the road... Sound was definitely audible in the recording and sounded like a higher pitch whine than in the inside. So I looked up other problems with the transfer case and I read that the chain in the transfer case has proven to loosen over time and I'm thinking that is the sound as many others have posted the same problem I am having on other forums and this was the source of the noise and vibration so I'm going to look into that soon and hopefully it's nothing that comes with a ridiculous price to fix.

DOES THE SOUND CHANGE IF YOU RUN IT IN 4WD FOR A SHORT DISTANCE?

THE MEDIC

I do not know at the moment but I ill see test it out tomorrow and see

i played with the 4 low this morning and when backing up i heard nothing and when going foward down the road i heard just a little whining. it does hit hard when changing gears tho and when turning there is very loud and hard popping that does not feel like the steering to me.

After playing around with the 4 low a little more, i am convinced it is the chain in the transfer case that is very loose. I put the transfer case into neutral and then put the jeep in drive and i didnt even have to hit the gas and i could hear it sounded just like my mini bike does when the chain on it is sagging the ground because it gets so loose. i have a hour drive to Appomattox this weekend and im relying on it to get me there and back home without a blowout like i have read about.

CHECK YOUR FLUID LEVEL IN IT (AND EVERYTHING ELSE!

THIS SHOULD EXPLAIN IT ALL!


IT MIGHT ALSO EXPLAIN HOW TO CHECK THE SLACK, WITHOUT EXPLORATORY SURGERY

THE MEDIC

Well i put 300 miles on the jeep this weekend and the sound and vibration has gotten worse. I can now also hear it just pulling up hills and straightaways. I tried jacking it up on stands and putting it in drive to see if i could replicate the sound and i could sightly hear what i think is the chain and i am still convinced it is the transfer case. I went to the site and looked at the repair manuals and i did not see anything about the transfer case. I have checked the transmission fluid and front differential fluid but the fill plug for the transfer case seems to be slightly striped out so i am almost scared to try and take it out. I think i may take it to the shop this week and see if they can figure it out.

PLUGGED IN YOUR INFO

1) WENT TO "AXLES" (FOUND TROUBLESHOOTING FOR DRIVE-TRAIN VIBRATIONS)......'AVE YA LOOKED THRU ALL OF THAT YET?

2) WENT TO TRANSMISSION AND TRANSFER CASE (IN WHICH THERE ARE 2 SEPARATE SECTIONS THAT HOLDS ALL OF THE INFO)

I SORTA "STRADDLED" THE "PLUG IN" PART TO SHOW YOU WHERE I WAS AT (UPPER HALF) AND THE MANUAL (LOWER HALF)

WHEN YOU GO BACK IN THERE---THE LOWER HALF WILL SCROLL LIKE FOREVER WITH AXLE/ TRANNY OR TRANSFER CASE INFO

I MADE 3 SCREEN SHOTS

---THE 1ST BEING THE DRIVETRAIN

---THE 2ND IS "PART ONE" OF THE TRANNY / TRANSFER CASE

---THE 3RD IS "PART TWO" OF THE TRANNY / TRANSFER CASE

THIS IS THE FACTORY INFO.....IT DON'T GET NO BETTER THAN THIS

I RECKON YOU KNOW HOW TO WORK "THE KNOWLEDGE BASE"????

LEMME KNOW IF THIS RE-MOTIVATES YOU

THE MEDIC

My jeep is a 1999 Grand Cherokee not the Cherokee and yes I looked all through every page about the driveline and transmission and differential and there was nothing about the transfer case and even the transmission they were talking about was not the one I have.

The information that the website provides is for the grand cherokee with an inline 6 cylinder not a V8 like I have. The transmission used for the i6 was the 45re and the transmission used for the V8 was the 45rfe. This is a common problem with websites, they only give the information for the most basic models of vehicles.

THAT'S ALL I COULD FIND

SORRY

THE MEDIC

It's okay. The other day the muffler and tailpipe got ripped out so now it's headed to the muffler shop soon and then it's soon to go to the local shop to see if they can get the noise figured out. Thanks for all your help I've learned allot! I'll try to keep the status of the jeep posted but as of now the sound is getting louder and vibrating much worse.

KEEP US POSTED---INFO SHARING GOES BOTH WAYS

THE MEDIC

Finally took out the front drive shaft today. It's definitely the transfer case end cv joint causing my issue.