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#367 of 1888 Re: Vibration
Jun 24, 2006 (7:00 am)
I purchased a 1999 Jeep Wrangler Sport. It has a 6" lift with 35" AT BFG's. When accelerating the jeep starts vibrating at 25 to 40 mph. I took it to the dealer and they said it was the tires and once they heat up it goes away. But, I had the tires checked out and they said it wasn't the tires. A couple of other mechanics told me it was something in the transmission. The dealer changed the U-Joints, the drive shaft and the Torque converter. And the problem still exists. The dealer tells me that the drive shaft is on a real bad angle and that is what is causing the vibration and is blaming the lift. I don't believe it. I think the transmission is shot. Since they changed the torque converter, there is another rattling noise coming from the transmission. It sounds to me like a lose nut on the heat shield. When I look under there, I noticed they stripped a bolt for the bellhousing cover. Is there anyone that could give me any insight on what the problem could be with the vibration/rattling noise?
#368 of 1888 Re: Vibration [francos]
Jun 24, 2006 (7:56 am)
I purchased a 1999 Jeep Wrangler Sport. It has a 6" lift with 35" AT BFG's. When accelerating the jeep starts vibrating at 25 to 40 mph..............The dealer tells me that the drive shaft is on a real bad angle and that is what is causing the vibration and is blaming the lift. I don't believe it.
Well maybe you don't believe it but I'd say he has a good chance of being correct. I'm sure you have stripped bolts and rattling parts, but they're most likely caused by the vibration and aren't the cause of it!
A six inch lift is difficult and/or expensive to set up for satisfactory use at highway speeds, and I've never heard anyone who says it's perfect under all conditions. A six inch lift with 35" tires is usually done to enable better offroad performance and it's not realistic to expect it to perform well on the highway too
There are things that can be done to place less strain on the propeller shafts but you'd have to explain what lift components you have on your Jeep first. Do remember that a six inch lift is an 'extreme' lift.
#369 of 1888 Re: Vibration [mac24]
Jun 24, 2006 (8:40 am)
thank you ... this is my first lifted jeep i have owned mostly ford p/u's with same size lifts and tires... I would realy like to leave the jeep the way it is but all i can tell you is that it has a pro comp lift... ... what i do see under is new coil springs, shocks and how can i say this... i guess i'll put it this way... looks to me like they welded some sort of tubes from the frame to the axles just below the shock mounts... The lift is a Pro comp explorer if that helps... Is there a way to lower the angle of the tranny or something to take some pressure off the shaft and tranny.... thank you so much for you help... If you need to know anything else let me know where to look ... Because Jeeps to me is a whole new ball game Thanks again
#370 of 1888 Re: Vibration [francos]
Jun 24, 2006 (12:03 pm)
I'm a bit puzzled here because although there is a Pro Comp Explorer 6" Suspension Lift which requires spring seats to be welded to the axles, the kit is for a YJ and it's to convert the suspension from leaves to coils. The YJ ended in '96, so that rules out your '99 Sport which is TJ.
Pro Comp Explorer make a TJ lift, but the highest is a 4" and it doesn't require anything to welded to the axles. From what I can see, neither kit makes provision for either raising the motor mounts or lowering the transfer case. Neither do they include, though they do recommend, a transfer case tailshaft conversion kit (commonly called a Slip Yoke Eliminator or SYE kit) which will allow the use of a rear propshaft with a double cardan joint (often incorrectly called a CV joint) like that fitted to the front.
It's also possible that either axle may need to be rotated upward, though this is not ideal. Without knowing exactly has or hasn't been done to your particular Jeep it's hard to take it much further. Also remember that every Jeep seem to respond a little differently to suspension modifications.
Probably the first thing to establish is whether you really have a '99 TJ, or some kind of converted YJ.
#371 of 1888 Re: Vibration [mac24]
Jun 24, 2006 (4:07 pm)
hello again: iwent outside to look at the lift .. there are brackets on the under side of the frame to me they look stock but i dont know what comes on a Jeep... thats why i thought that was part of the lift kit. and unless someone messed with the serial no# then it should be a 99 jeep tj... ( Hopefully) lol . now if it is a four inch lift will 35" tires fit on that?... i have a quadratec catalog and from what i can get out of it 35's only fit on a 6" lift... See i "really dont know. Please say that 35's can fit on a four inch lift... If they do then i have a 99 Jeep TJ like you said ... if not someone at the dealer is goona hear a rash of "POOP" from me.if everything is what you say it should be what would you recommend doing. Maybe putting a smaller tire like 33" or am i just fubared. Something tells me i should of just stuck with the Ford trucks ... i never had any problems with them and i went up to a total of 9" lifts with 38's. thank you so much for repleying again.. i hope to hear from you soon ...also the rattling sound i'm guessing was when they changed the torque conv... they stripped one of the nuts on the metal sheild that covers the bell housing...So when i was driving and appling gas that plate might of been vibrating really bad and the regular vibrating might of just made it worst, again im guessing at that what do you think? The tranny shifts fine nothing is binding up or getting stuck... I wish i knew more about Jeeps than i do... i really like this thing and want to keep it so you see i need to fix the problem or im never truely gonna enjoy it.... Franco
#372 of 1888 Re: Vibration [francos]
Jun 24, 2006 (7:03 pm)
You can fit 35's with a 4" lift and they'll be ok on the street but you can expect contact when the suspension articulates offroad.
You can't really compare a Wrangler to a Ford pickup. The Ford has a totally different suspension and a much longer wheelbase.
The best advice I can give you is to find a specialist 4x4 shop rather than a Jeep dealer, explain the vibration problem you're having, then have them put your Wrangler on a lift and explain to you what you have and don't have under there. Once you know the details of your lift you're then in a position to decide what alterations you may need to make.
#373 of 1888 jeep won't stay cranked
Jun 25, 2006 (1:04 pm)
i have a 88 jeep wrangler-it will crank-and stay started for about 5 min or less--i have replaced the fuel filter and fuel pump--can't figure what the problem is--any suggestion anyone--the jeep was down for about 2 months-due to transmission problem--it ran for a week-now this-
#374 of 1888 Re: jeep won't stay cranked [bamafever]
Jun 25, 2006 (2:21 pm)
It could either be an electrical component breaking down, or fuel related. You need to check if you have fuel in the carb when it stops, and whether or not you have a spark at plugs. You could also check on the quality of the fuel in your tank. Water in ther bottom of the float bowl of the carb would be a good clue.
#375 of 1888 Re: jeep won't stay cranked [mac24]
Jun 25, 2006 (4:32 pm)
i have removed the injector frrom carb and there was gas there. my carb does not have a bowl.
i have not been able to find out if i have a spark any where as of yet.
do you this that my coil could caused these problems.
the fuel in tank is fresh since i just replaced the fuel pump and filter on friday.
i had a reddish spark at the plug it died and stop at the same time.
#376 of 1888 Re: jeep won't stay cranked [bamafever]
Jun 25, 2006 (7:04 pm)
The spark should be a strong blue white color. Assuming that the plugs, wires, rotor and cap are all good then yes, the next suspect item would be the coil.