Still chasing down high speed vibrations here. Replaced rear lower control arms, ujoints, front driveshaft, front track bar.... hmm what else lol
Can anyone tell just by looking if my pinion angle looks alright? I ordered a gauge to check but it wont be in til next week. Just want to see if someone thinks i am on tje right track.
Its a 95 GC Laredo with 2 inch lift. Its been vibrating since i bought the truck, so i dont know if its been doing it since it was lifted, or if this is something new....
Oh i will add one more thing - starts to vibrate the whole truck at 90 kmh and up. Doesnt matter if i am on the throttle or in coast. If i go in a dip in the road (compresses the suspension a bit?) The vibration stops for a second. This is why i am suspecting pinion angle....
How's your Tire balance? 90KM/H is about 55MPH and that's when I used to get really bad vibration at high speeds. got my tires rebalanced and issue went away instantly.
Additionally, try removing front D/S. Unless you have the 249 TC. Do NOT remove front D/S on a 249.
That rear pinion angle looks wrong, though I'd need to see the t-case to know. The input yoke on the diff should be parallel to the output yoke of the t-case for a stock driveshaft.
Yeap, definitely wrong pinion angle. Rear output should be around 6°-7° down from horizontal, so the rear pinion angle should be the opposite pointing up from horizontal.
As for kg6mov's comment, I do agree. After the owner change this forum has become a lot worse. Same thing for Pirate4x4.
Apparently the 2 inch lift changed the pinion angle! I tried a tcase drop today to just try to match the angles and see if that helps. I used 3/4 inch and it made no difference at all. I got my angle gauge today and if i am placing it right i am still off 3 degrees. Maybe drop to 1 inch? I would rather not drop, but it i can match the angles and its still vibrating like crazy then i will look somewhere else.
Like i said, it was like this when i bought it and i have no idea if the dude just lived with it (its pretty bad at 90kmh!) Or if this is something new....
It was nice playing with the aftermarket switches on the dash and figuring out it has an e-locker in the rear though lol
If i get it up to speed and throw the tcase and transmission in neutral it still does it. So now it eliminates engine. I would think it eliminates tcase and tranny as well? Driveshafts would still be spinning so they are still in play i believe?
It feels like i am driving over rumble strips to give you an idea of how much it vibratea. Not just a slight annoying vibration lol
Ita stressing me out. I am dreaming of this friggin thing
Are we sure it's only 2"? That rear angle definitely looks too steep.
I've never had those problems with a small lift like that either.
Agreed that it's idiotic to ban certain web pages when the information is helpful.
Namely speed freaks .net
What are you running for tires? The 249 is sensitive to mismatched tires or uneven tire air pressure. If you measure the circumference they need to be within less than 3/8" of each other to keep the viscous coupling happy. If the V/C is already shot you can count on it wrecking pinion gears or other driveline parts. I bought mine cheap since the V/C had already lunched the front ring and pinion.
GW
P.S. KG, I meant no insult with the keyboard tourettes comment. I had no idea that content from other forums was censored. I believe that good information, regardless of the source should be shared.
I am running 31 bfg m/t . I think the vc is working right, everything i have read about the symptoms of a dead vc dont indicate mine is broken.
After work today i climbed under again (this has become my obsession lol). I took the weight off the front driveline and boom! I can move the pinion up and down. So my pinion bearings are shot. I would think this could cause a vibration since the drive shaft wont be spinning true anymore.....
As for the lift, pretty sure its a 2 inch. It has the 2 inch spacers. It also has an ARB bumper and winch, which is weighing the front down a bit. Any easy junkyard solution to level it out a bit?
First, before spending more money, look at the diff fluid. If the pinion is moving laterally, the fluid will probably resemble silver paint.
Try tightening the pinion nut to remove the play and get the pinion angles F/R correct. Doing those two things should get rid of a lot of the vibes for now. If the fluid was ok, you could get lucky with the pinion nut adjustment and go for awhile.
Front coil isolators give you about 3/8" of lift, they can be stacked. Or buy any of the PU lift levelling pucks meant for Jeep XJ/TJ/ZJ front.
However, don't goo to ohigh due to already having the 2" pucks in there. 2.5" is about the max. I'd go in front, in the rear even 1.75" is too much with the short OEM upper coil tubes.
Yes, a bad pinion bearing can and will cause driveline vibes, especially if you can actually move the pinion up and down.
Levelling it out didnt help. I think its time to accept that its the pinion bearings.
I am tempted to pull the front driveshaft and drive a block at 90kmh to see if it goes away. My wife is going to chop off my manhood if i drop more money and dont fix the problem lol. But dont want to risk burning up the 249.
Driving it around the block at any reasonable speed without a front shaft is the kiss of death for the first gen 249.
If there is ANY play at all in the pinion the pinion is ****ED, you need to fix it before you can get much else useful diagnosis done. From what you are describing the pinion would totally cause the vibes you're feeling.
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