TrailMaster '98 Explorer lift Driveshaft Problems

[Djohnson]

After I installed the Trailmaster lift I soon found out that the stock driveshaft would not work. The stock joint that was at the transfer case would not cover the additional angle that the lift created.

I then began working on the alternitive to buying the $675.00 shaft that Trailmaster was selling.


I decided that I needed a regular double cardan joint at the transfer case. I made an adapter that would allow a four bolt pattern drive shaft bolt up to out six bolt transfer case.


Right now I have the shaft off of the truck. It drives very smooth. No vibrations at all.

As soon as I put the new shaft on, I get a slight vibration around 55 MPH and up. The vibration is not very bad. It feels as if I am running some very meaty tires.

I have checked all the obvious items...(balance of shaft and balance of adapter).

The model below is the adapter and a drawing of the shaft.

I don't know what to try next.

Thanks for any help.

DJ

 

[riffman]

if you were to go straight out with the adapter (which, is AWESOME that you made it) its going to create more of an extreme driveshaft angle. You would need to keep your pinion agles more the same front to back. Also, there are certain "limitations" to how fast a shaft should be spinning at greater angles....now i think i remember you being an engineer from our discusions before, so you know a hell of a lot more about actual tollerances that they can go through than i do....but here is a list that i found from www.therangerstation.com

DRIVESHAFT RPM - MAX. NORMAL OPERATING ANGLE
5000 - 3.25º
4500 - 3.67º
4000 - 4.25º
3500 - 5.00º
3000 - 5.83º
2500 - 7.00º
2000 - 8.67º
1500 - 11.5º

now im not sure that this is your problem....a cheaper alternative than going with thier shaft is haveing a custom one made. There is a guy in clinton that will make you one for around $140. Shoot me an e-mail if you want his name and stuff.

Good luck!!!

 

[stadx2]

Hey DJ,

You should seriously think about marketing that adapter! I just installed Superlift's 4 inch Kit on my '98 and have been having a hell of a time finding a driveline shop that can fab that adapter. Even Tom Woods didn't
have one for me. And theres no way I'm getting ripped off by Trailmaster by paying $675 for theirs!

Darren
Littleton, CO
____________________________________________
98 Explorer Limited V8

-Front 4 inch Superlift(Ranger)+1 inch Torsion Twist
-Rear 5.5 inch Superlift SOA
-KKM Air Intake

 

[Djohnson]

Dead Link Removed
I measured the angle of the front shaft today and it is about 10.5 Degrees.

I then calculated the shaft RPM by taking the tire revolutions per mile(613) times (4), because I have 4.10 gears.

That comes out to 2453 RPMs on the shaft at 60 MPH.

According to the riffman's chart I am exceeding the Max normal operating angle.

What now!

Concerning the adapter creating an increased angle of the shaft. Without the adapter the shaft will have one less degree of slope. Making it 9.50 Degrees this angle would still max out at around 1800 RPMs.

I might need to sell the rights to that adatper in order to pay for the Trailmaster shaft.

 

[riffman]

hmmm....sounds rough man!!!!

the only possible solution i can think of, is a combination of some. Use a longer driveshaft without the adapter, and see if you can lower your transfercase any. Since jeeps have such short driveshafts, they have to lower thiers when they go taller....maybe you can do the same thing. I have never heard of this happening, but im sure that you can figure it out!!

lol...making adapters and whatnot is really cool though!! Where did you make it?! Are you using like CAD CAM or somthing?

 

[Djohnson]

I made it at work. We call these little projects "Government Jobs".

I also do CNC programming for a machine shop using CAD/CAM. I made this part on a live tooling lathe. The live tooling allowed me to drill both bolt circles concintric to each other.

What it the deal with a Vacuum Disconect Axle Lock. I saw it in my Chilton's manual. It says that is is in place of the AutoHubs on the 95+. I can not find any such component on my Explorer.

 

[riffman]

its under the wheels, where the hubs on the 91-94's would be. i think its like the same system that Rams have....

 

[felsmann]

Not to burst your bubble, the Company that made my front shaft bought the adaptor from Ford, this is an existing part. However, I too have that vibration proble, at about 70-75 MPH (I have 33" tires with 4.56 gears) I am taking the truck next week to the shop to have them rebalance the shaft.

My vibration is like a humming sound that comes and goes in intervals of about 3 seconds. It kind of sucks. I did not use to hear it as much until today that I picked up the truck with new gears, so now I hit the shaft vibrating RPM's at a lower speed (75 instead of 85) therefore I experience it more often.

Hopefulloy you will find a solution since you have the engineering brains!!!

 

[felsmann]

Interesting article

I don't know that this helps any, but while researching on the net I found these:

http://www.hicklin.com/vibration.html

Dead Link Removed

Dead Link Removed

 

[gage]

Drive shaft

I had this problem. I have a 4" susp and a 4" body. I would hear clicking coming from the front drive shaft. I had tried the standard UV joint on both ends and it did not work at all. The local clutch and U- joint place made me a stock looking UV on front and CV back but lengthened the drive shaft by 1". This has helped me with the angle tremendously. NO more noise and vibrations. All for the cost of $225.00.

 

[mikefox]

Vacuum disconnect....

DJohnson, the vacuum disconnect you talked about is only on 95-96. They use it because they have the 4WD selector with 2wd, 4auto and 4lo. 97 they did away with the disconnect because they went with 4auto, 4hi and 4lo. No need to disconnect the front when you use 4auto. Hope this makes sense.

 

[Djohnson]

Thanks Mikefox.

Gage
I still am not totally clear on what they did to your explorer. Have you measured the angle of your shaft?
I guess I don't understand how they lengthend the shaft when the distance between the transfer case and the differential is fixed. This distance on mine is around 30.9 inches.

 

[gage]

Drive shaft

Yes my length stock was about 30.5" But when you lengthen the shaft it puts less stress on the CV side that is limiting the angle due to our lift kits.

I was told that ford had to go with the CV joint because the angle had to be within (if I can remember) 2 or so degrees of each other on a standard UV joint shaft but because of the short wheelbase they could not achieve this so they had to go with a CV style.

What is happening is the CV is riding at the very end of its limits within the joint and when you lengthen it it puts the ball bearings close to optimum riding level (closer to the middle). there is play when you install the shaft you can pull or push it approximately 3" but when installed the angle will pull the shaft to much and possibly pull the shaft out of the bearings. stock w/lift you are riding at the cusp with it lengthen the bearings have someplace to go other than what mine looks like now.I will try to take some pics of mine that has a lot of ware close to the end of the joint. give me couple of days to get this done. And don't make fun of me when you see them! They went BOOM!!

 

[Djohnson]

Gage is your lift the '98 - '01 Explorer Trailmaster lift?

Or is it a ranger kit?

 

[gage]

lift

Explorer lift kit! I will take some pics of the CV joint tomorrow (friday).

 

[gage]

Lift

I assume that ( if your like me ) you may have taken the CV ( Constant Velocity ) joint apart at one time or another. They may differ slightly but theory remains. You have six or so large bearings the are assembled in a cube form, two bearings on each side. But as the shaft is pulled or pushed though the joint the bearings may contract or separate from each other. the bearings are contained within this cylinder that rides between the outer part of the joint and the gear attached to the shaft. the assembly looks like a set of weird spider gears. When you move the shaft the bearings slide in the unit. BUT they only go so far, If you pull hard enough YOU WILL PULL THE SHAFT OUT from the the bearings. allowing the bearings to fall where the want to in the joint "DON'T DO THIS". The bearings when setup correctly should ride near the middle for the joint but when we pull it to make it work at the angle that the 4" lift requires. then it will be at the limit.

I now it sounds strange but it will work. With the stock shaft I had to almost force the shaft into the front diff. mount. After the addition of the 1" I had angle to spare.

 

[Djohnson]

Gage,

Who did you get to lengthen your shaft? When I asked around everyone said that they could no do it because that one end has the (6) bolt circle. I am not familar with the ballancing equipment but it seems that you could just chuck up on the whole joint in a lathe.

Did you have any suprises when doing the install?

 

[gage]

Greg @ Clutch & U-Joint/Proven Force
7474 Co Rd 81 N BRKLYN PK MN 55428-1229

(763) 425-7474

There is a gear that has a C-clip holding on your shaft within that CV joint. The shaft itself has to be lengthened (not the CV joint ) Give them a call if nothing else they might be able to point you in the right direction. Also might be able to explain this better.

I seen a reply about JEEPS in this discussion Jeeps have Double CV joints on both ends now to compensate for the angle.

CV joints can withstand higher rpms than standard UV joint with Balance issues. I will still get PICS for you to see what is happening in there.

Go to my Pics and you will find a couple of drawings that I crudely made to help until I get the chance to get the pics.

No the install went great! I had more than 1" below the diff hookup to play with. Before the mod. I had to force down about 1/2" to get it bolted in. Probably why it went BOOM!

Dead Link Removed

I hope that link worked!!!!!!!!!!

 

[felsmann]

Just came back from driveline shop!

I just cam back from the driveline shop, they rebalanced my shaft, and I still get the vibration.

I found out that the shaft that I have now, which is no a modofication of the stock, but a fully redisgned new shaft, has a CV joint going out of the transfer case, and a U joint into the axle.

The guy at the shop does not know what elese it could be, so I'm out on a limb.

Can you guys describe what your vibration feels like? Mine is like a harmonic rumbling that starts at about 70 MPH.

 

[gage]

Shaft

I would guess that you are no longer using the adaptor that you referred to earlier, If so get rid of it. My first replacement was with an adaptor and two UV joints on a slip shaft and had the same vibration that you described. Low pitch loud hum for a period of 2-3 seconds and then a higher pitch lower level hum for 1-2 seconds. If it has the slip shaft where the shaft itself can slide up and down get rid of that as well.

I am not a sales person for clutch and U-joint I work on networks for a living but I would give them a call.

Have you tried Tom Woods in ?"Utah" I think!

Do you have a vibration without the front drive shaft installed?

Can we try this if you have not?

If you don't have the vibration after removal, then it is most definitely the front shaft. If not I would think that it is possible that it may be a bad set of gears you had installed or the installation itself.

I assume you checked you tires!

Get back us about poss. front drive shaft removal. and we can hit it from there.

You must forgive me I would just like to cover the basics first.