I think my U-joints are shot

66fastback · 04-16-1999, 09:57 AM

At about 40 MPH the vibration starts. It just gets worse as I go faster. By 50 MPH or so the vibration gets so bad, the whole car seems to resonate. I have had a slight vibration for a long time, it got worse when I put in the 3.40 gears, and the past few days it got bad enough that I can't stand to drive on the highway. How can I check to be SURE it's the U-joints? Could it be something else? Any help is greatly appreciated.

------------------
66 GT Fastback 5.0, 5-speed, 3.40 gears, Fuel Injection soon

Jerry · 04-16-1999, 10:57 AM

Hey cool stang, I got a 67 GT Fastback myself. Anyway, you can usually hear the u joints clunk when you accelerate or deaccelerate. You might try going under the car, grabbing the drive shaft and twisting it back and forth to check for abnormal movement in the joints.
Dont forget the obvious things like your tires being out of balance etc. Good Luck

hehhehmule · 04-16-1999, 11:50 AM

I agree with Jerry, try and twist your driveshaft and observe anything unusual. You might also put it in gear and push on it, alot of times even in drive they'll move some and thunk if the u's are bad. I once thought I had a joint going bad and it turned out to be a plug wire off causing my vibration, just a thought. Good luck. BTW I too have a 67 fastback Jerry, it's an S code GTA.

Dark Knight · 04-16-1999, 01:47 PM

Check the fan clutch too, if you are running the one that comes with the 5.0... had mine go bad.. thought it was the u-joints too...
Can tell,,,try spinning it with the belt on... should turn...

------------------
84 convt,'95 302, performer
3.55's, underdrives shorties
and a '68 stang that WAS nasty ;-)

66fastback · 04-17-1999, 03:54 AM

Thanks for the help guys. I was given a link to a good site on drivelines. The vibration I am getting sounds just like my pinion angle is way off. Guess it's time to replace those saggy rear springs. Anyone know of a quality set/ good place to purchase?

Jerry · 04-19-1999, 11:05 AM

hehhehmule, Actually I have two 67 fastbacks (yeah I love them). The GT is a K code the other is a very original C code. The S code is a 390, right? Anyway fastbacks rule, later.

hehhehmule · 04-19-1999, 01:05 PM

Yeah, that's right Jerry, it's the 390. A 67 K-code fastback huh? Damn that's sweet and the C's a 2v right? I've got a 65 solid lifter 271hp in my truck, love that engine. I understand it's real uncommon for a 67, congradulations. I had a C-code years back. Boy those 67 FB lines are cool huh?

Jerry · 04-19-1999, 03:41 PM

hehhehmule, Well the story gets alittle sad. The GT was through a lot of hands (translation used & abused) before I got the car. I never got a chance to experience the original engine. There is a plain jane 289 4 bbl in it now. The C's original engine was lost due to my own stupidity. I worked at a marina many years ago. I replaced the engine and the marina accidentally gave the engine to the junk man. Good news is I'm putting a 460 in the car. Any experience with 460's
As far as FB lines, only two other cars equal or come close - 66 charger & 63 to 67 vett.

hehhehmule · 04-20-1999, 09:41 AM

Can't say I've ever messed with a 385 series much Jerry. I can tell you a FE 390 is a mighty tight fit in a 67 and I think the 460 is a bit wider. As for your GT, anything with a K on it is worth its weight. Just hold on to it till you can find a K engine and you'll be set. They're great they feel alot like a 5.0 but the sound is so much more visceral.

Dark Knight · 04-20-1999, 11:21 AM

460's rock.. am putting one in my 68 coupe..can get 500hp out of one with out much problem.. FMS has a 460 short block for about 1500, around 560 hp..cool, huh?

------------------
84 convt,'95 302, performer
3.55's, underdrives shorties
and a '68 stang that WAS nasty ;-)

Jerry · 04-20-1999, 02:57 PM

Dark Knight
Oh yeah! I got my 460 out of a 76 Lincoln. In the process of tearing it down. Hoping for a basic rebuild. not much money. I've read a few articles about the swap. Do you have the motor mounts, trans mount, drive shaft, or headers?

04-16-1999, 09:57 AM	#1
66fastback Registered Member Join Date: Mar 1999 Location: Dallas, TX Posts: 208	I think my U-joints are shot At about 40 MPH the vibration starts. It just gets worse as I go faster. By 50 MPH or so the vibration gets so bad, the whole car seems to resonate. I have had a slight vibration for a long time, it got worse when I put in the 3.40 gears, and the past few days it got bad enough that I can't stand to drive on the highway. How can I check to be SURE it's the U-joints? Could it be something else? Any help is greatly appreciated. ------------------ 66 GT Fastback 5.0, 5-speed, 3.40 gears, Fuel Injection soon

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
100 shot with stock injectors?? ok?	Coupe50h	Power Adders	7	11-13-2003 10:35 PM
A-arm bushings and Ball joints	glxstang	Windsor Power	3	07-22-2002 01:22 PM
Ball Joints	gray ghost86	Windsor Power	4	06-06-2002 11:08 AM
150 SHOT of NITROUS KICKS A$$!!!!	FordFasteR	Stang Stories	20	08-15-2001 12:27 PM
NOS shot and system....	St_Brawler	Modular Madness	2	07-17-2000 03:49 PM

04-16-1999, 10:57 AM	#2
Jerry Registered Member Join Date: Nov 1998 Location: lakewood, nj Posts: 23	Hey cool stang, I got a 67 GT Fastback myself. Anyway, you can usually hear the u joints clunk when you accelerate or deaccelerate. You might try going under the car, grabbing the drive shaft and twisting it back and forth to check for abnormal movement in the joints. Dont forget the obvious things like your tires being out of balance etc. Good Luck

04-16-1999, 11:50 AM	#3
hehhehmule Registered Member Join Date: Sep 1998 Location: Nashville TN Posts: 608	I agree with Jerry, try and twist your driveshaft and observe anything unusual. You might also put it in gear and push on it, alot of times even in drive they'll move some and thunk if the u's are bad. I once thought I had a joint going bad and it turned out to be a plug wire off causing my vibration, just a thought. Good luck. BTW I too have a 67 fastback Jerry, it's an S code GTA.

04-16-1999, 01:47 PM	#4
Dark Knight Registered Member Join Date: Oct 1998 Location: Az Posts: 854	Check the fan clutch too, if you are running the one that comes with the 5.0... had mine go bad.. thought it was the u-joints too... Can tell,,,try spinning it with the belt on... should turn... ------------------ 84 convt,'95 302, performer 3.55's, underdrives shorties and a '68 stang that WAS nasty ;-)

04-17-1999, 03:54 AM	#5
66fastback Registered Member Join Date: Mar 1999 Location: Dallas, TX Posts: 208	Thanks for the help guys. I was given a link to a good site on drivelines. The vibration I am getting sounds just like my pinion angle is way off. Guess it's time to replace those saggy rear springs. Anyone know of a quality set/ good place to purchase?

04-19-1999, 11:05 AM	#6
Jerry Registered Member Join Date: Nov 1998 Location: lakewood, nj Posts: 23	hehhehmule, Actually I have two 67 fastbacks (yeah I love them). The GT is a K code the other is a very original C code. The S code is a 390, right? Anyway fastbacks rule, later.

04-19-1999, 01:05 PM	#7
hehhehmule Registered Member Join Date: Sep 1998 Location: Nashville TN Posts: 608	Yeah, that's right Jerry, it's the 390. A 67 K-code fastback huh? Damn that's sweet and the C's a 2v right? I've got a 65 solid lifter 271hp in my truck, love that engine. I understand it's real uncommon for a 67, congradulations. I had a C-code years back. Boy those 67 FB lines are cool huh?

04-19-1999, 03:41 PM	#8
Jerry Registered Member Join Date: Nov 1998 Location: lakewood, nj Posts: 23	hehhehmule, Well the story gets alittle sad. The GT was through a lot of hands (translation used & abused) before I got the car. I never got a chance to experience the original engine. There is a plain jane 289 4 bbl in it now. The C's original engine was lost due to my own stupidity. I worked at a marina many years ago. I replaced the engine and the marina accidentally gave the engine to the junk man. Good news is I'm putting a 460 in the car. Any experience with 460's As far as FB lines, only two other cars equal or come close - 66 charger & 63 to 67 vett.

04-20-1999, 09:41 AM	#9
hehhehmule Registered Member Join Date: Sep 1998 Location: Nashville TN Posts: 608	Can't say I've ever messed with a 385 series much Jerry. I can tell you a FE 390 is a mighty tight fit in a 67 and I think the 460 is a bit wider. As for your GT, anything with a K on it is worth its weight. Just hold on to it till you can find a K engine and you'll be set. They're great they feel alot like a 5.0 but the sound is so much more visceral.

04-20-1999, 11:21 AM	#10
Dark Knight Registered Member Join Date: Oct 1998 Location: Az Posts: 854	460's rock.. am putting one in my 68 coupe..can get 500hp out of one with out much problem.. FMS has a 460 short block for about 1500, around 560 hp..cool, huh? ------------------ 84 convt,'95 302, performer 3.55's, underdrives shorties and a '68 stang that WAS nasty ;-)

04-20-1999, 02:57 PM	#11
Jerry Registered Member Join Date: Nov 1998 Location: lakewood, nj Posts: 23	Dark Knight Oh yeah! I got my 460 out of a 76 Lincoln. In the process of tearing it down. Hoping for a basic rebuild. not much money. I've read a few articles about the swap. Do you have the motor mounts, trans mount, drive shaft, or headers?