Spankrjs' 1984 Long Term Project

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
More driving, more problems, more work :crazy:

Had the tires re-balanced last weekend, no problems. Went to have the alignment adjusted, problem. Two of the tie rod ends had a hair bit of play. No big deal, usually, BUT:

I installed a Rugged Ridge Heavy Duty tie rod/drag link kit on this Scrambler a couple of year ago, with a tie rod/drag link flip. No problem there, per say. The problem - Rugged Ridge tie rod ends use a 7/8" threaded portion, the part that threads into the tubes. Well, they advertise it as 7/8", but it is actually M22x1.5. The tapered part of the rod ends is supposedly the same as a stock Jeep CJ. Moog still makes/sells one of these rod ends, I believe the LH version. Moog used to make the RH version, but they do not anymore. I spent all day last Saturday looking through old paper parts store books for replacement RH rod ends with the spec's I needed, I could not find any. The only RH stuff I could find would have the correct tapered part spec's, but they would be attached to a drag link, or are the drag link. So, I had to order replacements from Rugged Ridge. Not the end of the world, but I do not like not being able to buy off the shelf replacement parts.

One other "issue" - looking at the spec's for the Moog LH version, on all the important tapered part stuff, it was not a 100% match for stock CJ parts. It was close, but not exact. The LH version of this rod end is the same as a 2005 TJ rod end at the pitman arm. If you compare the spec to this rod end to a stock CJ end, there are some differences. Rugged Ridge sells these rod ends a direct replacement for all their HD steering kits, i.e. Cherokees, TJ's, and CJ's. But, they are not a 100% match.

Which brings up this issue, maybe. A while back, I removed the tie rod/drag link from the passenger side knuckle when i installed a new steering box. The tapered insert that holds the tie rod to the knuckle on the passenger side fell out. The drag link one was fine. The insert was slightly damaged. I reinstalled it, with some Sleeve Retainer. A new insert would have been a good idea, but I did not have one at that time.

So, when I pulled it apart this time, the same insert fell out. This time, I installed a new insert. The old inset was damaged. The first time the insert fell out, I thought that maybe I had messed up the knuckle hole with the reamer, reamed too deep. Nope. The new insert was a tight fit and I had to tap it into final position slightly. The other two insert are still tight into the knuckle bores.

Damaged insert, new insert.

IMG_20190127_145025022_HDR.jpg

I have used these OK4WD inserts for over 30,000 miles on my red Scrambler, no problem. On my Red Scrambler, I purchased the entire kit from OK4WD, inserts, reamer, and the their HD tie rod/drag link kit, with ends. One major difference - The OK4WD kit uses stock CJ rod ends, IIRC they are 11/16 threaded portion. So, off the shelf replacement CJ parts will work. I know this because I had to change out the less then stellar OK4WD rod ends for some replacements. I removed all the rod ends, no knuckle inserts fell out or were damaged.

So, I "think" the stock CJ rod end taper portion is a better fit for the OK4WD inserts :twocents:

So, in hind sight, I would have bought another kit from OK4WD. They use stock tie rod ends, easy to get replacement parts. Now, you do lose the benefit of a M22x1.5 threaded portion of the Rugged Ridge kit vs the 11/16 threaded portion of a stock CJ tie rod end. But realistically, I am wheeling a Dana 30 with 33" tires. If I bend an 11/16 tie rod end threaded portion, I am going to tear up a crap load of other stuff first.

So, my suggestion, buy the stuff from OK4WD.

Now, Rugged Ridge does offer a 5 year warranty on their parts. Except for wear and tear. Which tie rod ends do. So, they won't warranty them anyway. So, wasted warranty advantage :twocents:

The two tie rod ends had very slight play, the drag link ends were fine. But I replaced all four rod ends for new ones. So, now there are two good spares, a RH and a LH, and two emergency spares with a hair bit of play. The new rod ends eliminated the very, very, very, very slight bit of play at center. So, steering is 100% good, tires are good.

But, I still had some slight drive line vibration from the rear. This has been more noticeable since I installed the full hard top. When I originally set the rear pinion angle, when I swapped in the rear CV driveshaft, the pinion was either one degree lower then the driveshaft or equal. Well, with some miles on the leaf springs and the added weight of the hard top, the pinion was now a degree higher then the rear drive shaft. Not good.

Checking the angles on my uneven off road driveway, the pinion was up 11, driveshaft down 10. So, taking a cue from Jake White, I pulled out the 2.5 degree pinon wedge shims. This dropped the pinion to up 9.5, driveshaft down to 14. So, pinion down 4.5 degrees. Well, hats off to Jake, this all but eliminated all the rear drive line vibration. There is still just the slightest bit, so I might try a one degree shim, but which way, pinion down some more or up a hair? These softer springs must really allow for some pinion climb, I wouldn't think 4 degrees worth, but pulling the shims sure helped a bunch. Maybe this is a V8 thing? On my six cylinder powered red Scrambler, rear CV, same leaf springs (except missing the extra leaf I added to the V8 Scrambler rear packs), the pinion angle is almost equal to the driveshaft angle, maybe a hair down, no vibration.

The one degree shims are the "slip in" kind, not like the good steel shims I have been using that use the leaf spring center pin to bolt them to the pack. But, one degree is not much, and it will be easier to install/swap them around for tuning purposes. But first, more driving, they might not be worth the hassle of installing them :twocents:

Plan on driving this one to Baton Rouge this weekend to go play with more Jeeps, and driving it to work this week. Quick picture of the whole Scrambler, seems like all I have been posting pictures of are parts LOL

IMG_20190128_104709479_HDR.jpg
 
Last edited:

John N

Addicted....Ex-SOA VP
LIFETIME
CJ-8.com Member
SOA Member
City
Rockville
State
VA
You still haven’t found that rock we put inside that back tire....😂🤣😛?
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
So, after removing the 2.5 degree wedges, the pinion is 4.5 degrees down at rest. After driving it all day yesterday, around town, highways, and the interstate, it is completely vibration free UNTIL 65 mph. Once you hit 65 mph, like magic, it start to vibrate. Not a terrible vibration, but it is there.

It is definitely a torque produced vibration, if you throw it in neutral or let off gas, it goes away.

At 65 mph in drive, the vibration is slightly more then in overdrive. In drive, I would presume more torque is powering through the driveshaft. So, 65 in drive, shift it to overdrive, vibration lessons. I would assume the pinion is lowering back down some with the shift to overdrive.

Or, am I too low to start with, and the vibration just starts at 65 mph due to driveshaft rotation speed causing the not right pinion angle to start vibrating?

I think it is too low. So, I am going to wedge the pinion up 1 degree, see if the vibration lessens. If it does, great. If the vibration increases, I will flip the wedge, in effect add 1 degree additional downward angle, and test.

Either up or down, 1 degree should make a difference :fingerscrossed::twocents::shrug:
 

wm69

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
God's Country
State
AR
Watching this with great interest as I have a vibration in my tan CJ that appears from about 57mph to 65. Doesn't vibrate any other time, and just like yours, it's bad when under power, goes away when coasting.
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
Watching this with great interest as I have a vibration in my tan CJ that appears from about 57mph to 65. Doesn't vibrate any other time, and just like yours, it's bad when under power, goes away when coasting.
Yep, it is aggravating, for sure :banghead:

Green Scrambler, before lift, no vibrations. After 2" lift/shackles, and CV shaft, high speed vibration, pinion angle needs re- adjusting still :crazy:
Red Scrambler 4.5" lift/AX15/CV shaft, no vibrations (6 cylinder) :thumbsup:
Tan Scrambler, with old 4" Superlift springs, no bad vibes, with RE springs with added main leaf, annoying vibe, with CV shaft :crazy:

One out of three ain't bad :rotfl:

My above post is kind of confusing. Remember, this is with a CV shaft, regular shaft is different :twocents:

With pinion 1 degree higher then driveshaft, vibration. This makes sense, it should never be higher, since the pinion will want to climb.

So, took out the 2.5 degrees shims, pinion is now 4.5 degrees lower then driveshaft. I think this is too low. So, no vibrations until 65, which is good. I am thinking it is vibrating above 65 because even though the pinion is rotating upward, it is not rotating upward 4.5 degrees. So, once the driveshaft is spinning this fast, the misalignment between the pinion u-joint and the driveshaft is too great, causing a vibration.

So, hopefully adding 1 degree of upward pinion angle, reducing the total misalignment at rest to around 3-3.5 degrees, will put a closer to zero misalignment between the pinion u-joint and driveshaft above 65 mph resulting in no vibration:fingerscrossed:

If the reduced misalignment at rest caused by adding 1 degree of upward pinion angle INCREASES the vibration, then I would assume the pinion is indeed rotating upward more then 4.5 degrees at 65mph. If this is the case, then I will rotate the shim 180 degrees, rotating the pinion down to 5.5 degrees, and road test. I do not think this is the case.

The vibration is way reduced with the pinion being down at rest since I pulled the 2.5 degree shims which were causing the pinion to be one degree higher then the driveshaft. I am hoping that I am just a hair too far down now :fingerscrossed:

Pinion bearing and output shaft bearings feel fine. All u joints good. Axle and diff bearings feel fine. Tires just re-balanced. Pretty sure this is an angle vibration, especially since changing the angle changed/reduced the vibration.

The old super stiff Super Lift springs did not cause vibrations. I am assuming they were so stiff that there was minimal pinion rotation. The RE springs, even with an added extra main leaf, are way softer then the Superlift springs. They ride great. Not too squishy, not bone jarring, just right. I am assuming this is just one of the added joys of a V8 Jeep with soft springs :thumbsup: Hopefully, I will figure it out soon.

The trip to South Dakota, and back, no vibrations, so it must have been pretty close to correct back then. I am assuming the springs have softened up slightly, added weight of full hard top, have pushed the angles out of the acceptable range :twocents::fingerscrossed:
 

Belizeit

CJ-8 Member
CJ-8.com Member
City
River Ridge
State
La
OMG ! That would drive me crazy after changing things up. I might just stick to 64 mph. But that would be pretty easy for me since I only can do that as max speed because I only have a 4 banger. Maybe when I change out my rebuilt 258 with fuel injection I will realize also, I have a problem with higher speeds. :(
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
OMG ! That would drive me crazy after changing things up. I might just stick to 64 mph. But that would be pretty easy for me since I only can do that as max speed because I only have a 4 banger. Maybe when I change out my rebuilt 258 with fuel injection I will realize also, I have a problem with higher speeds. :(
Just got to work through it, not too hard, just tedious :thumbsup:
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
OK, installed the one degree shim, and road tested. With the pinion rotated up an additional degree, I should be starting out around 3-3.5 degrees down. I did not check with the angle finder. It is not an exact linear adjustment, because as you rotate the pinion up, you are slightly decreasing the driveshaft angle, which makes the change greater then the angle of the shim. Anyway, results:

The vibration now does not start to around 70-75 mph. So, I am going in the right direction.

The vibration is no longer responsive to torque, i.e. up to 70 mph in drive or overdrive, no vibration, including shifting back and forth from drive to overdrive at 65-70 mph.

So, I am thinking I still need to rotate the pinion up slightly, maybe pull the 1 degree shim and try a 1.5 degree shim. I should have ordered some 1.5 degree shims :banghead: OR, I can slightly space down the skid plate with a thick washer, decreasing the driveshaft angle, effectively lessening the angle difference between the pinion and driveshaft.

I know it sounds crazy talking about 1-1.5 degree changes, especially considering we are talking about a Jeep CJ, but it makes a huge difference :twocents: You have to remember, I, Jeep CJ owners, have about the worst combination of drive line factors to overcome:

1) short wheel base, steeper driveshaft angle, even stock, compared to a full size truck
2) lifted, increasing the driveshaft angle
3) soft springs, a bit more pinion wind up
4) 4L60 transmission is pretty long, decreasing the length of the stock driveshaft, increasing the drive line angles
5) 4.10 gears/33" tires means a higher driveshaft RPM, compared to a stock 3.31 gear/30" tire combination

The last point is interesting. Spicer has a chart telling you max operating angles of u-joints at a given shaft RPM. More angle, less RPM. This explains why sometimes you can throw a 4" lift/33" tires on a Jeep, keep the stock 2.73/3.31 gears, and have no vibration. The driveshaft is not spinning that fast. Put in deeper gears, it starts vibrating due to shaft speed. Even without a CV, you can have deep axle gears (4.88/5.13), with large enough tires (38"+), you can drive probably up to 60-65 mph because the shaft is not spinning that fast. Put smaller tires on, it will shake you to pieces at lower speeds.

I kind of proved this. No shim, so I had probably a 3.5 degree angle on the pinion u-joint at 65 mph, vibration (lower shaft speed)
One degree shim, say a 2.5 degree pinion u-joint angle, vibration pushed back to 70-75 mph (higher shaft speed)
So, say a 1.5 degree shim, 1.5 degree pinion u-joint angle, vibration might be pushed back to 80-85 mph (even higher shaft speed)

Even with a "CV" shaft, if it is operating at a steep enough angle, even with the pinion u-joint at 0 degrees to the driveshaft, given enough shaft RPM, it will vibrate. Example, say you have a 25 degree driveshaft angle, transfer case output shaft at 5 degrees down. So, 20 degree operating angle, each u-joint in the CV is operating at 10 degrees. Given enough shaft RPM, it will vibrate. IIRC, Spicer wants a MAX 3 degree angle, or say even 5 degrees. A stock CJ is at that. You lift them, you exceed the angles. A CV most of the time will help, with say a less then 6" lift. You get much past that, with deep enough gears/high enough shaft RPM, it will vibrate.

Theoretically, if I swapped in 3.54/3.73 gears, I would lower my shaft RPM, so the vibration would not present itself until probably over 90 mph.

When I say vibration, mine is slight. It is not shaking the whole Jeep, but I can feel it a bit in my butt/floor pan. With the amount of lift, and other factors, I know it should be 100% smooth. It was, before the springs settled slightly and I reinstalled the full hard top. Just needs a bit more adjusting :twocents:

Picture of the steel 2.5 degree shim vs the aluminum 1 degree shim. I prefer steel, but I can not find a steel shim less then 2 degrees.

IMG_20190129_163746309.jpg

The other issue - this shim is NOT pinned to the leaf pack like the steel shim. It simply slips around the center pin head. Because it is one degree, it is pretty thin, so I still get 100% engagement between the center pin head/hole in spring perch. If it was say 2 degrees or more, it would be thicker, and a taller center pin head, or center pin head spacer, would be needed to get full engagement.

Thickness difference. Ittsy bittsies sometimes make a huge difference:

IMG_20190129_163811134.jpg

Installed, looking from above:

IMG_20190129_170600137.jpg

IF I was looking for another project to do right now, longer "anti-wrap" style spring perches would be a good idea. The stock perches are still fine, not rusty or rounded, but a longer/thicker perch would help eliminate some pinion climb. Long term solution - shim the pinion to where it is good, record the angle. Weld on new perches to the correct angle. Re-do the transmission mount/spacers to allow for some minor drive line angle adjustment there, where it is easier to adjust. Remember, softer springs will settle a bit more depending on the amount of crap you have in the bed. If you set it up "perfect" empty, when you load it up, the angles could be off a hair. I have been adjusting this one with a full 20 gallon tank of gas and about 200 pounds of crap in the bed. I would rather have it "perfect" for how it is loaded on long cross country trips, and maybe have a hair bit of vibration when 100% empty :twocents:

When I had the Superlift springs, it took 1,500 pounds of gravel to get the suspension to compress 1", so no chance of enough of a drive line angle change to cause a vibration, loaded or empty. The RE springs are softer, so they will compress more easily. I would rather have the softer springs, better ride quality, and have to deal with a bit more angle tuning :twocents: This is probably why the factory offered different spring rates :twocents:
 

Kane

CJ-8 Member
CJ-8.com Member
City
Berlin
State
ct
There another factor in play here as well with a 2 u-joint shaft. Both ends of the drive shaft need to be at the same angle from the part they are attached to being the transfer case and the axle. If the angles are not the same to each other then the elliptical pattern they both rotate through will be different which causes a harmonic vibration. Basically if the pinion to the shaft was a 3 degrees then the shaft to the transfer case had to be at 3 degrees as well. You may not get rid of the vibration 100% if you do not factor this in so angling your t-case down may help more than you realize. This is one of the reason why a 3 u joint style CV drive shaft works so well. The CV portion of the shaft by design keeps the two front u joints at equal angles from each other effectively cancelling out the vibration and then you just set the pinion angle to the shaft at 1-2 degrees. My old CJ5 had a 16 inch drive shaft on a 3 inch lift. The CV shaft was the only solution because I could not get the two angles at a good spot with the short shaft length and even if they were close I still was past the maximum work angle for high speed use.
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
There another factor in play here as well with a 2 u-joint shaft. Both ends of the drive shaft need to be at the same angle from the part they are attached to being the transfer case and the axle. If the angles are not the same to each other then the elliptical pattern they both rotate through will be different which causes a harmonic vibration. Basically if the pinion to the shaft was a 3 degrees then the shaft to the transfer case had to be at 3 degrees as well. You may not get rid of the vibration 100% if you do not factor this in so angling your t-case down may help more than you realize. This is one of the reason why a 3 u joint style CV drive shaft works so well. The CV portion of the shaft by design keeps the two front u joints at equal angles from each other effectively cancelling out the vibration and then you just set the pinion angle to the shaft at 1-2 degrees. My old CJ5 had a 16 inch drive shaft on a 3 inch lift. The CV shaft was the only solution because I could not get the two angles at a good spot with the short shaft length and even if they were close I still was past the maximum work angle for high speed use.

Yes :thumbsup: I already have a CV shaft, just trying to get the pinion u-joint angle to be "correct" at interstate speeds :thumbsup:

On this Scrambler, and my green Scrambler, I adjusted the two u-joint shafts to have the "opposite but equal" angles". But, with the driveshaft angle, the u-joints were operating at over 10 degrees. No vibration until you went over 55 mph. The u-joints can't cope with that degree of operating angle with a high shaft RPM. Low speeds, fine, high speeds, nope.
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
Drove to Baton Rouge this weekend, worked on some of JeepAddict's stuff, drove it back home last night. No problems :thumbsup:

On the way there, drove 75-80 mph, except for about 30 minutes of bumper to bumper traffic in new Orleans (5pm on a Friday, who'd a thought LOL) 16.5 mpg. Forgot to record the miles when I started back home, but no traffic, so probably over 17 mpg at the same speeds.

As for the slight vibration, it is basically road surface induced. I have been driving it within 20 miles of my house. The interstate around here has heavy traffic, so ruts and wear and tear. Once I got away from home, the vibration changes depending on road surface. On concrete roads/bridges, no vibration. So, mostly happy with that.

The full top is a bit worse (i.e. top heavy) then the half top with high speeds and heavy winds. With the half top, I added an extra main leaf to each rear pack, made it way better. The full top is much heavier, and makes the sides of the Scrambler like big boards, so more sensitive to cross winds. Not terrible, but it was better handling with the half top. Like I said before, I'll take the soft springs any day over stiff springs. The ride is very nice in this one. IF I was going to drive a whole bunch cross country with the full hard top, I might look into a rear sway bar.

Kind of funny to talk about handling, I think about my LJ, bone stock (no lift/30" tires/rear sway bar), handles very well, but you can still feel the strong cross winds. This Scrambler has 5.5" of lift, with 33" tires, still handles well. If you drive the Scrambler at 70, crosswinds are less of an issue.

One other note since adding the full hard top - you can hear the fuel pump. With the 1/2 top, since the pump was on the rear cross member, you couldn't really here it. Now, with it bolted to the body near the back of the passenger side wheel well, under the full hard top, you can hear it hum. It is quiet at first, gets louder the longer it runs. You can't hear it at interstate speeds, too much wind noise. One other interesting thing - when you get down to 5 gallons of gas left in the 20 gallon tank, it gets louder, especially while cornering. I am assuming that the stock fuel pickup tube comes uncovered with the fuel splashing around. Those GM in tank fuel can things seem like the hot ticket :twocents:

With the Scrambler parked on JeepAddicts immaculately clean concrete driveway over the weekend, I only left one drip spot, from the power steering pump. I think I overfilled it awhile back, so all of the high speed driving forced the excess fluid out the hole in the cap. The cap was very dirty/oily. The stick measured "FULL" at cold, so should be good to go.

This was the first "long" trip in one of my Scramblers since I went through chemo last year, so felt good to be back in the saddle, get over all the worries/anxiety. Glad the Scrambler performed well.

Not too many pictures, this was just the crap I came back with, all my tools and stuff. On the way there, I had a complete suspension set up in the back, too. The full hard top is very nice for hauling lots of stuff:

IMG_20190204_074142861.jpg

And back under the Harbor Freight canopy thing, still need to unload it:

IMG_20190204_074253627.jpg

Kind of bitter sweet, this might have been my last trip with this one, might be getting a new owner this week, but will stay with the CJ8 family, and be loved.
 

Ron84cj

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
West Bend
State
WI
Bummer. I guess not a complete shock. You were talking about possibly selling it a while ago. I kind of hoped you wouldn't. So are you going to bring up the red one in August?
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
Bummer. I guess not a complete shock. You were talking about possibly selling it a while ago. I kind of hoped you wouldn't. So are you going to bring up the red one in August?
If I can make it up there his year, either the Red or Green Scrambler :thumbsup: Hope to make it up there this year, depends on cancer stuff :fingerscrossed:
 
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