Hey guys..85 k5 blazer with (i think) an 8 inch lift. Have a pretty good vibration from 30mph on up..looks to me whoever did the lift got the pinion angle all out of wack but im not real keen on driveline issues. Havent had a chance to measure it yet but what are your thoughts on this setup? Is a cv shaft going to be my only option or can this be done with a fairly simple adjustment? Trying to get rid of the vibration and am worried about taking this thing on any long trips down the interstate and loosing a u joint or worse. I only drive it about 10 miles each way to work right now all under 55mph (mostly 35 and 45). Im starting to wonder if i should even be driving it at all now. Your thoughts?
CK5
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Need help..pinion angle? (Pics)
- Thread starter Chevelle
- Start date
A) Your pictures didnt work. Just red X's
B) In general: Anything over 4" of lift on a Blazer wheelbase means you have to go CV to get something that will survive.
Also: go read this to learn about driveshaft stuff
http://www.pirate4x4.com/tech/billavista/PR-shaft/index.html
B) In general: Anything over 4" of lift on a Blazer wheelbase means you have to go CV to get something that will survive.
Also: go read this to learn about driveshaft stuff
http://www.pirate4x4.com/tech/billavista/PR-shaft/index.html
fyi go read at pirate4x4 just dont hang out there .
and yes 4"-up on short wheel base like blazers almost always - c/v shaft rear .
and yes 4"-up on short wheel base like blazers almost always - c/v shaft rear .
Sometimes, even with a 4" lift, you need a CV shaft. But with 8" lift you will be better off upgrading to the CV shaft instead of trying to get the right angles without it. You and your K5 will be very happy.
Sorry hopefully this works
https://ibb.co/ch9tNk
https://ibb.co/eQi68Q
https://ibb.co/bPrF2k
https://ibb.co/mHb4v5
Damn..so im guessing im in for sticker shock between the $450 shaft and labor to drop and split the case for the new output shaft and shimming the rear end to point toward the tc shaft..so im looking at $700-1200 im guessing depending on the shop. Id do it myself if i didnt life on a mountain in tennessee with a gravel driveway and minimal tools with me. Ughh. Not sure i want to go through all that brain damage.
https://ibb.co/ch9tNk
https://ibb.co/eQi68Q
https://ibb.co/bPrF2k
https://ibb.co/mHb4v5
Damn..so im guessing im in for sticker shock between the $450 shaft and labor to drop and split the case for the new output shaft and shimming the rear end to point toward the tc shaft..so im looking at $700-1200 im guessing depending on the shop. Id do it myself if i didnt life on a mountain in tennessee with a gravel driveway and minimal tools with me. Ughh. Not sure i want to go through all that brain damage.
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yep they do .
looks a bit steep to me . and also looks to be about bottomed out in the slip yoke .
were going to need more info to point you in the right direction .
t-case = ?
driveline angles = ? going to need to get a angle gauge to check them .
and looks like someone swapped in 3/4 or 1ton axles . the rear is a 14ff rear . if stock its a 1350 u-joint yoke .
looks a bit steep to me . and also looks to be about bottomed out in the slip yoke .
were going to need more info to point you in the right direction .
t-case = ?
driveline angles = ? going to need to get a angle gauge to check them .
and looks like someone swapped in 3/4 or 1ton axles . the rear is a 14ff rear . if stock its a 1350 u-joint yoke .
Ok. So yes you are seriously out of whack on those joints. Odds are one or both u joints are already damaged from improper angle balancing. The operating angles need to be matched for a 2 joint shaft.
Hard to say, but that doesnt look like 8 inches of lift.
Having a slip yoke on the output of the t-case complicates going to a CV shaft. Do some research on slip yoke eliminators.
Hard to say, but that doesnt look like 8 inches of lift.
Having a slip yoke on the output of the t-case complicates going to a CV shaft. Do some research on slip yoke eliminators.
what size tires do you have on it ?
might be better in the end to lower the blazer down a bit .
whats the end use of the vehicle .?
what type of off road use do you plan ?
might be better in the end to lower the blazer down a bit .
whats the end use of the vehicle .?
what type of off road use do you plan ?
mark sargent
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try this app it'll help you correct the angles
https://www.dropbox.com/s/xh2kt0yy9qcwczb/DAA.exe?dl=0
Ok guys quick update..btw thanks to all of you for the insight!! As requested ive got a little more info if it helps..really hoping theres a more inexpensive solution as i dont offroad this thing very much if at all..honestly i would not have got a blazer that was lifted if it wasnt such a good deal for what is actually a very clean, rust free truck.
Anyway..to get to the point..the TC is a 208 and my overall drive shaft angle is 18 degrees with 14 at the tc and 8 at the rear diff. Another thing i was hoping you could tell me from the pics..where do i stand as far as the slip yoke engagement? I know sweet k30 said it looks about bottomed out..can you elaborate a bit? I understand how it works but could that mean this may be a lengthened drive shaft? A friend of mine who runs rock crawlers said yeah its off but doesnt look severe enough to panic and not drive it. Any thoughts? Thanks again guys.
Anyway..to get to the point..the TC is a 208 and my overall drive shaft angle is 18 degrees with 14 at the tc and 8 at the rear diff. Another thing i was hoping you could tell me from the pics..where do i stand as far as the slip yoke engagement? I know sweet k30 said it looks about bottomed out..can you elaborate a bit? I understand how it works but could that mean this may be a lengthened drive shaft? A friend of mine who runs rock crawlers said yeah its off but doesnt look severe enough to panic and not drive it. Any thoughts? Thanks again guys.
Ok, here is my best shot at your problems. The angles on your u-joints must be within 1/2-1 degree of each other. When the shaft spins the outside of the u-joint is moving faster than the inside. In your case the top of the u-joint at the T-case and the bottom of the u-joint at the differential. When the front and rear angles are the same (or very close) they cancel each other's vibration. To remedy your problem get a angle finder from Home Depot or Lowes. The circular type, empire makes a good one about $10-$15. Measure the flat spot where the slip yoke comes out of the T-case and the flat end of the differential where the pinion shaft comes out. Those angle should be with in 1/2-1 degree of each other. There are a couple of ways to change those angles. at the T-case a lowering kit is what you need. Basically heavy duty bushings that go between the frame and cross member with longer grade 8 bolts. At the differential you need some angle shims. Those go between the leaf springs and the axle. You can find them online for $15-$25 a piece ( steel are better than aluminum).Hey guys..85 k5 blazer with (i think) an 8 inch lift. Have a pretty good vibration from 30mph on up..looks to me whoever did the lift got the pinion angle all out of wack but im not real keen on driveline issues. Havent had a chance to measure it yet but what are your thoughts on this setup? Is a cv shaft going to be my only option or can this be done with a fairly simple adjustment? Trying to get rid of the vibration and am worried about taking this thing on any long trips down the interstate and loosing a u joint or worse. I only drive it about 10 miles each way to work right now all under 55mph (mostly 35 and 45). Im starting to wonder if i should even be driving it at all now. Your thoughts?
What I can tell from your pics is you need to lower your T-case maybe 1 1/2"- 2" that u-joint has a pretty big angle on it. At the differential you have almost no angle. Either one could fail, if the back failed completely you could lose your drive shaft and most if not all your fluid in the T-case. If the front failed completely at worst you could pole vault the back of the vehicle or drive the drive shaft through the gas tank (worst case scenario).
The second problem the slip joint is too far into the T-case. This need to be fixed first, as lowering the T-case will push the slip yoke farther into the T-case and you don't have much room left. The only way I know of fixing that is a shorter drive shaft. The othe way is a slip yoke eliminator (try JB conversions) which also will require a new drive shaft.
I had many of the same problems you have (sounds like it) and have done extensive research on it on line. There are some good videos on you tube on drive line problems. My solution was a lowering kit inch and a half I think and my drive shaft professionally balanced with new U-joints pressed on by the drive line shop. Oh and I have a 6" lift on my Blazer with no CV joints and no slip yoke eliminator, but someday I will.
He's right. You "probably" wont have a catastrophic ujoint failure and spit the shaft out if you stay at lower speeds. But, you need to get it fixed. At the very least you will be destroying u-joints. There is no speed at which it isnt a problem, you just cant feel it in the driver seat at lower speeds.
It looks like you have rear lift blocks. If you ever plan to change that, now is the time. My guess is that a t-case drop will help, but it wont completely solve the problem. And it hurts your front driveshaft angles. Check and see how close you are to hitting the stops on the front shaft (in the CV) before you go that route. Axle shims work great, but you really shouldnt stack them with lift blocks. Better than shims is to cut off the spring perches, rotate the axle, and weld them back on. Based on the driveshaft being too far in already, I dont think you can get out of this without some modification to the shaft.
Btw: Its very hard to "pole vault," there's a Mythbusters episode on that (with a car). Driveshaft through the gas tank is definitely plausible though.
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do NOT drop the t-case . it creates way more problems then it fixes in the end . there has been lots of members here who have removed and fixed the driveline the correct way and been much more happy in the end.
Is there anything i can do as far as a driveshaft that is a direct bolt in where i dont have to split the case? I understand that if i go the cv route something about having to change the output shaft?? What about slip yoke eliminators...the way to go?? Trying to keep all this under $600..if its going to be over a grand..i very well may sell this damn thing..im not going through all this sh*t just to get rid of a vibration. Hell for that kind of money im halfway to a whole new longblock for my other truck. How involved is it to take the lift kit off and lower the whole damn truck? Im running 36" tires now...not sure how low i can go..and to be honest not sure what size lift is even on this thing
4 inch lift with some fender fang chopping and you would be fine. Might get away with no fender chopping if don't go off road much.
no real 208 slip yoke eliminator kit I know of that's bolt in . so that shoots that out of the options.
were are you located ? ? might help get you options in your area .
were are you located ? ? might help get you options in your area .
ah o.k.
I don't know of much there my self.
they do offer c/v shafts for slip yoke. a member here just got one in the last week or so . I don't recall who tho sorry .
I don't know of much there my self.
they do offer c/v shafts for slip yoke. a member here just got one in the last week or so . I don't recall who tho sorry .
I am the guy sweet was referring to on the cv slip shaft recently. Best bet is to find local shop and take them the truck have them see if cv slip will work. You still might need to do shims to get it perfect but you can get them through DIY4X.
Here is my recent cv shaft
