Vibration on Accel and Decel only-need advice (1 Viewer)

[chukarhiker]

I found a lot of vibration threads but none with these exact symptoms

Following are my symptoms:

Vibration is only when the driveline is not under a load and only occurs when I accelerate or decelerate (does not do it unless in gear).

It “grrr’s” when I let off of the gas or give it gas but just until the drivetrain is either pulling or the engine is in compression.

RPM or MPH make no difference-it will do it at any speed over 15mph and in any gear.

I can feel it in the floor (especially the passenger floor) and the transfer shifter.

If I lock the Center Diff it gets louder and vibrates more.

There are no leaks around pinion seal or anywhere else.

I have 83K miles on the truck now.

What we have done to test:

Pulled the PS slider-no change in vibration (did help the Cat vibration though).

Tried to replicate the vibration at a stop with foot on brake in drive and reverse and no vibration.

We put on the rack at Toyota (buddy is the service manger) and were able to replicate the noise but not tell where it was coming from although sounded like the front.

We pulled the front drive shaft; took a drive and the vibration totally went away.

No movement in/out/up or down when we push and pull on the front drive shaft.

The Toyota mechanic thinks it is the pinion bearing in the front diff even though when he checked the magnet on the drain plug he said there was no more metal than normal although he said the gear oil was a little old looking.

The Toyota mechanic thinks my next step should be to have them check all the bearings in the front diff which I didn’t get a price on yet but assume it will not be cheap even with my discount and my buddy/service manager says to “just drive it and don’t worry about it”.

The front drive shaft has the original u-joints but I just noticed that the 2 grease fittings on the front u-joints and spline are 90 degrees from the rear joints fitting-is this normal?.

Should I “just drive it”? Would like to get rid of the noise if I could tho and w/o great expense.

Thanks, Jim

 

[Romer]

The front drive shaft is suppose to be 90 deg out of phase.

I am assuming this is the 97 witrh the 3 inch lift, any spacers on the front?

With a properly balanced drive shaft and new U joints I developed the Grrr with the 1 inch spacers. went away when I took them out. I have the OME 2.5" lift.

Sounds like the drive-shaft pinion angle problem, but could be a loose at the Front Diff pinion. Others smarter in this area than I will have to chime in.

Would like to know if you solve it and how. It's always nice to see how it ends up, good or bad!

 

[chukarhiker]

The front drive shaft is suppose to be 90 deg out of phase.

I am assuming this is the 97 witrh the 3 inch lift, any spacers on the front?

With a properly balanced drive shaft and new U joints I developed the Grrr with the 1 inch spacers. went away when I took them out. I have the OME 2.5" lift.

Sounds like the drive-shaft pinion angle problem, but could be a loose at the Front Diff pinion. Others smarter in this area than I will have to chime in.

Would like to know if you solve it and how. It's always nice to see how it ends up, good or bad!

Thanx for the responce Romer.

Yes it is the "97.
A loose "what" at the Front Diff? Would the noise with a drive-shaft pinion angle problem still have the same symptoms when the truck is on the rack? Mine did.

Looking at the reciepts from the PO (I bought the truck already lifted) I see that the caster correction bushings; Adjustable front spacers and 1.5" front sway bar
drop blocks were among items purchased and installed at his Toyota dealer.
Are these the spacers you are refering to?

Jim

 

[Romer]

No, I was talking about the 1 inch Mr. Gasket spacers that get added to the top of the coil.

I think it would have the same problem on the lift because the angle would still be ther.

I heard that (but don't know) if your pinion flange (Part drive shaft bolts to on frt axle) is a little loose it will cause a similar problem. I don't know if thats true and hopefully someone more knowledgeable will step up and comment.

Some people go with the double cardon drive shaft to fix the issue. If you are thinking of going that route, call Slee and talk to them. They sell it, but will give you the straight poop on what else you could try. That's always a good reason to do business with them.

 

[elmariachi]

I have 83K miles on the truck now.
We pulled the front drive shaft; took a drive and the vibration totally went away.
No movement in/out/up or down when we push and pull on the front drive shaft.

I doubt its the pinion bearing at those miles. If it were mine, before tearing into the axle I'd take the front driveshaft to a driveline shop and have them look at it. Even though you didn't notice anything by moving it by hand, I have had shafts that appeared to have no play and still found to have a bad or excessively worn u-joint.

 

[Romer]

On the spacers, take a look at the top of the front coils and see if the coil goes directly into the housing. Use the below link to see before and after spacer shots to see if you have one. I took mine out and my Grrrrr went away.

This was after having the U joints replaced and the axle balanced:

https://forum.ih8mud.com/showthread.php?t=51526

 

[elmariachi]

I took mine out and my Grrrrr went away.
This was after having the U joints replaced and the axle balanced

That's the other side of the coin: Some of these trucks just vibrate with lift and spacers, thus the need to go to a double cardan driveshaft www.sleeoffroad.com.

I hate to admit it but my front DS was vibrating so I removed it and I have a severly worn u-joint. Unfortunately, in this little town of Houston with 6 million people and 11 driveline specialty shops, no one can or will work on a Toyota shaft. So I am waiting in a trip to Dallas to have it fixed.

 

[Romer]

Fixed the link for you Jim. ) don't work well in a URL. Need a space

http://www.sleeoffroad.com/products/products_drivetrain_main.htm#Double Cardan Front Driveshaft

 

[elmariachi]

Fixed the link for you Jim. ) don't work well in a URL.

Hey, what the heck do I know anyway????

 

[chukarhiker]

Thanx again guys!

Romer-

I went to your link and I do have spacers but they are different than yours in that they are an aluminum looking material and are mounted on a threaded stop (see list of parts below—the adjustable front spacers from Slee??). It appears that I can adjust the height by turning the spacer on the threaded stop—the spacer has holes that you could place some kind of tool in and turn I think. The spacers are now 1.25 inches down from the top on the DS and 0.75 inches down on the PS. Should I try adjusting them and if so in which direction and what kind of tool? I looked on Slee’s site which has a link to the adjustable front spacers but it appears to be disabled—his other front spacers are labled “discontinued” are the adjustable ones also?

In looking at the parts the PO put on the truck am now thinking I may have a 6” lift??
I have 39.5 inches to the bottom of the flare in the front and 38 inches in the rear with about 150 pounds of gear in the rear and a heavy stout bumper in front and stout ¾ roof rack.

Jim—if the spacer adjustment doesn’t pan out I will take the drive shaft to be balanced and new joints installed as a first step.

I also just measured the angle of the front drive shaft at 7 degrees 7 minutes (7.12 degrees) based on 4.13 inches drop over the 33 inch length of the drive shaft. Is this in specs?

Following is a list of major parts the PO bought for the lift as taken from Slee and MAF receipts in 2000:

MAF
2-OME 850 MD-HVY COIL SPRINGS $136
2-OME 863 MD-HVY COIL SPRINGS $136
2-OME N73 MD-HVY SHOCKS $149
2-OME N74 MD-HVY SHOCKS $149
2-OME CA77 CASTER KIT $65

SLEE
SOF1030-SOF FRONT CONTROL ARMS $745
SOF1011-SOF 1.5” FRONT SWAYBAR BLOCKS $36
SOF1023-SOF ADJUSTABLE FRONT SPACERS $590
SOF1009A-SOF REAR SWAYBAR BRACKETS $36
Jim

 

[Romer]

I don't know anything about those spacers. You could go get a spring compression tool, lots of auto parts stores loan them. And just take the spacers out and see if that has any impact. Takes about an hour for both sides the first time and 30 minutes once you have done it.

 

[chukarhiker]

Grrrrr is gone.

We installed the Slee Cardan front Drive Shaft and my Grrr quit right now and has been gone for 160 miles now. Soo nice to hear the silence and soo glad I didnt have Toyota tear into the front diff.

Jim

 

[semlin]

glad your problem went away. it sounds like you had a particularly bad case of the "grrs".

i don't remember slee adjustable spacers and if they were that spendy I'm guessing they were before my time, but they sound kind of cool. your rig has an ome "heavy" lift plus the aforesaid spacers. It sounds like it is about a 3 to 3.5" lift. why do you think it is a 6" lift?

 

[sleeoffroad]

Adjustable spacers were 1.75" on minimum setting. I am not sure where Jim has them set now.

 

[chukarhiker]

glad your problem went away. it sounds like you had a particularly bad case of the "grrs".

i don't remember slee adjustable spacers and if they were that spendy I'm guessing they were before my time, but they sound kind of cool. your rig has an ome "heavy" lift plus the aforesaid spacers. It sounds like it is about a 3 to 3.5" lift. why do you think it is a 6" lift?

Christo estimated my lift to be 5 or 6" when I discussed my mods with him. Dont know how it relates but the spacers are about 1.25" apart which would be 3" (1.25 + 1.75) I guess per Christo's post.

What is the method to measure your lift anyway--do you measure from the center of the hub to the flare or??? and what is stock?

Jim