Vibration

Hi,

Just took the Jeep out to bring a chair to my Mom in the retirement residence. It is located about 60 km from home. I notice a small vibration that wasn't there last summer. The vibration translate to a low rumble in a cab. Its always there but way more noticeable once I hit 50 - 55 miles per hour or when I decelerate. Its not engine related because I coast it in neutral to see if it would go away and it didn't. So I figure, cheapest thing first... to get my NTD tire balance (they have no weights on them - so I suppose they were never balanced by the PO). However, when I got home... I push on the top of the front tire without jacking up the Jeep and I notice a small play... what do you think? Wheel bearing or king pin bearing? How do I tell the difference?

 

Where to start? The first thing I would do is to check out the driveshaft(s). Ujoints, slip joints, output from the transfer case, yokes into the differentials. Tires, flat spots from sitting, ice or snow in the wheels or balance as you mentioned? Even the amount of air in the tires can cause an issue and the type of tires. I don't think the kingpin bearings would cause a vibration, just mess with your steering. Something you probably need to address next summer.
Good luck.

 

I agree with uncamonkey on all the things to check, but kingpin bearings or wheel bearings can cause a vibration. I'd check the cause of the play first. Jack up the front axle so tires are off the ground. Wiggle the tire at 12 o'clock and 6 o'clock. If just the wheel and hub moves it's wheel bearings. If the wheel and knuckle move together it's kingpin bearings.

 

"Low rumble in the cab"

I'd check the UJs first.

 

Ok, will jack up the jeep this weekend and see where the play is from - I'll also check the rear U-Joint. I had to change the seal in the rear differential last summer - things looked ok at that time but I'm now wondering if I didn't install the drive shaft the same way it came off?

 

You probably had the looseness in your wheel bearings and/or king pins last summer, but the imbalance due to storage flatspots in your Nylon carcass tires are causing a vibration now. It's not uncommon on a 6:00-16 to be 4-6 ounces out of balance after 6 months of storage. The 'morning sickness' goes away pretty quick though.

Once you are sure that the 'play' is not indicative of a safety concern with anything falling off, drive the jeep for 60-100 miles before getting the tires balanced or you will balance in the flat spots.

 

Good point, I'll get her on a lift like everyone say - check drive shaft - U-joint and bearing/King pin first to make sure nothing will fall off. One question - if I tug on the tire by grabbing it from the top and bottom and try to rock it - I should not get ANY play at all correct?

 

Correct.

 

Is it a once per tire revolution shake, or a roar? The driveshaft will vibrate 4.27 times the frequency of a tire balance vibration if you are running 4.27 gears.

 

Ok I drove it to the local do-it-yourself garage - got it on the hoist and check + I took the opportunity to grease everything while it was up.

1- U Joint for drive shafts are all OK - no play at all.
2- grabbing the tire top and bottom and wiggling it shows a small play (both side but more on the passenger side) - May be between 1/8 to 1/4 inch - no more. I don't think the knuckle move but the hub did for sure.
3- grabbing at 3 and 9 o'clock shows most of the play at the Bell Crank - I already knew it was so-so last year so I guess its time.

I got 4 wheel bearing (National part # 013-0587-4) at my local part store. While I'm at it should I change the king pin bearing? Are they usually available locally or do I have to order from a Jeep specialist? I don't have the part number for those.

I guess there is not way to tell what is the Bellcrank size for my 66 (7/8 or 1-1/8) for ordering without taking it apart correct?

PS> Trying to cut down on ordering from the USA if I can due to our low dollar, shipping + duty. Saying that - I have to add that its a good time to come visit Canada.

 

Thats funny.. i remember ur jeep for sale on kiliji! U would have the smaller 7/8s shaft ! My 1967 is still 7/8s

 

Its been a good Jeep thus far... had typical symptoms of not been driven often enough (i.e. dried out seals). The PO had it plated as historic which severely limits the outings. It's now plated and insured as a classic ride. I still have some limits on the driving like regular shopping trip or drive to and from work etc.. but I have no issues taking it out for a fun ride. I pile up between 3000-4000 km per year thus far, about the same as my old Dnepr motorcycle. I find it neat that it is a Canadian built Jeep (Windsor Ontario) and ended up in the USA and now its back here. I have the paper record of its first 1000 miles inspection and oil change at Bob Bass Inc. Raleigh N.C. - you can go on google street view and see the dealership where it was originally sold in 1966. It cost $4.00 of labor, $3.85 for filter and $3.25 for oil - total was $11.22 including a 0.12 tax.
$
My biggest issue right now is the wheel bearing/bell crank. Next will be the leaky front tranny "seal" which bothers me the most. I'm planning to do the clutch at the same time although nothing is currently wrong with it. Then I'll fiddle some more with the Solex carb... it has a annoying hesitation when you get going at a street light.

It's a never ending thing... that's why I bought it in the first place.