Pinion Angles?

jonosranger · 09-14-2009, 02:30 PM

Ok guys i have been fighting this for a while now. I have always had a slight vibration since i put this 3550 in my car. The rear suspension would go down so much when i lanched my car that the drive shaft would hit the floor board. Worn out shocks and no pinion snubber, Replaced shocks and snubber. Last thursday nite I took my car to the track on a 17" drag radial to play around. My second pass i launched at about 4500 and bent twisted my driveshaft to the point i could see it move 3/8 of an inch or better when i jacked the car up and spun the tire. So i Brought it home and changed driveshafts. Its driveable but still has a kinda bad vibration. My dad said something about pinion angles so i just glanced a the back on the trans and it is sticking up in the air. Im gonna go home and try to measure them today. Vibration is the worst when you are driving and u are not accelerating and not coasting but in between. I hope somebody can chime in. O and my car has solid motor mounts a stock trans mount, and factory 5 poly bushinged non adj. control arms with stock rear springs.

86nu · 09-14-2009, 04:04 PM

did it vibrate before the swap, solid mounts will transfer a lot of harshness, as for the pinion angle -1 or -2 is what we set ours at so when its on the ground its close to 0 or 1

waypastcrazy · 09-14-2009, 05:48 PM

Yea keep your foot out of it!lmao! In general 2 to 3 at tranny. -2 to 3 on pinion springs and shocks can effect it greatly. R u sure the driveshaft is correct length as in not to long with the 3550 trans. Lol good luck.

Craig K. · 09-15-2009, 06:17 AM

It has been a while since I set my pinnion angle but as I recall -2 to -3 is what I went with, you will need adjustable control arms to do this though.

The solid motor mount will transfer some vibration, if you clutch and coast does the vibration go away, though this would also take the load away from the diff.

jonosranger · 09-15-2009, 06:22 AM

Quote:

Originally Posted by 86nu

did it vibrate before the swap, solid mounts will transfer a lot of harshness, as for the pinion angle -1 or -2 is what we set ours at so when its on the ground its close to 0 or 1

Not this bad it didnt.

Quote:

Originally Posted by waypastcrazy

Yea keep your foot out of it!lmao! In general 2 to 3 at tranny. -2 to 3 on pinion springs and shocks can effect it greatly. R u sure the driveshaft is correct length as in not to long with the 3550 trans. Lol good luck.

Well you kno lol

As far as length i believe it is. guess i should check that lol. O I forgot to mention that the driveshaft is binding up into itself. As in the rear flange is hitting the driveshaft. Its hard to explain.

jonosranger · 09-15-2009, 06:31 AM

Quote:

Originally Posted by Craig K.

It has been a while since I set my pinnion angle but as I recall -2 to -3 is what I went with, you will need adjustable control arms to do this though.

The solid motor mount will transfer some vibration, if you clutch and coast does the vibration go away, though this would also take the load away from
the diff.

No it gets worse. I just put my 4.10 gear in cause the pinion was slightly loose so i thought i would just go ahead and get that over with and fix that.

waypastcrazy · 09-15-2009, 09:34 AM

I can take a look when I get home if ya want. But it cost ya a beer. Lol

jonosranger · 09-15-2009, 09:50 AM

Quote:

Originally Posted by waypastcrazy

I can take a look when I get home if ya want. But it cost ya a beer. Lol

lol Ill buy u a whole dam 12 pack

When will you be home??

waypastcrazy · 09-15-2009, 10:31 AM

Quote:

Originally Posted by jonosranger

lol Ill buy u a whole dam 12 pack

When will you be home??

idk maybe fri

jonosranger · 09-15-2009, 11:08 AM

Quote:

Originally Posted by waypastcrazy

idk maybe fri

will you be off all weekend? If so i could trailer my car down to your house?? it dont matter to me i just need to get it fixed lol

09-14-2009, 02:30 PM	#1
jonosranger Boost! Its wats 4 dinner Join Date: Mar 2009 Location: Bridgeport,AL Posts: 811	Pinion Angles? Ok guys i have been fighting this for a while now. I have always had a slight vibration since i put this 3550 in my car. The rear suspension would go down so much when i lanched my car that the drive shaft would hit the floor board. Worn out shocks and no pinion snubber, Replaced shocks and snubber. Last thursday nite I took my car to the track on a 17" drag radial to play around. My second pass i launched at about 4500 and bent twisted my driveshaft to the point i could see it move 3/8 of an inch or better when i jacked the car up and spun the tire. So i Brought it home and changed driveshafts. Its driveable but still has a kinda bad vibration. My dad said something about pinion angles so i just glanced a the back on the trans and it is sticking up in the air. Im gonna go home and try to measure them today. Vibration is the worst when you are driving and u are not accelerating and not coasting but in between. I hope somebody can chime in. O and my car has solid motor mounts a stock trans mount, and factory 5 poly bushinged non adj. control arms with stock rear springs. __________________ 06 F150 crew cab 4x4 leveled on 35s 94 Lincoln Mark VIII, 3000 stall, shift kit, 3.73, hub swaped, 98 cobra wheels 06 yLincoln Zephyr- Wifeys DD

09-14-2009, 04:04 PM	#2
86nu Senior Member Join Date: May 2007 Location: orlando florida Posts: 165	did it vibrate before the swap, solid mounts will transfer a lot of harshness, as for the pinion angle -1 or -2 is what we set ours at so when its on the ground its close to 0 or 1 __________________ 86 Coupe aka the battle ship H/C/I, Nitrous, bla bla bla all on a 351

09-14-2009, 05:48 PM	#3
waypastcrazy ADDICTED TO SMALL BLOCKS Join Date: Jan 2007 Location: lookout mt Posts: 1,757	Yea keep your foot out of it!lmao! In general 2 to 3 at tranny. -2 to 3 on pinion springs and shocks can effect it greatly. R u sure the driveshaft is correct length as in not to long with the 3550 trans. Lol good luck. __________________ http://alabamaopencarry.com/forum/index.php One of StreetStangs class clowns! Status:slow as hell! NORTH EAST ALABAMA STANGS

09-15-2009, 06:17 AM	#4
Craig K. Nothing new here Join Date: Dec 2004 Location: Senoia, GA Posts: 2,990	It has been a while since I set my pinnion angle but as I recall -2 to -3 is what I went with, you will need adjustable control arms to do this though. The solid motor mount will transfer some vibration, if you clutch and coast does the vibration go away, though this would also take the load away from the diff. __________________ 1974 Triumph TR6 1985 Monte Carlo SS 1986 Mustang GT 2011 KIA Optima GTS

09-15-2009, 09:34 AM	#7
waypastcrazy ADDICTED TO SMALL BLOCKS Join Date: Jan 2007 Location: lookout mt Posts: 1,757	I can take a look when I get home if ya want. But it cost ya a beer. Lol __________________ http://alabamaopencarry.com/forum/index.php One of StreetStangs class clowns! Status:slow as hell! NORTH EAST ALABAMA STANGS