Bad Birfield? (1 Viewer)

[80Diff]

I just finished repairing a bad inner seal on the front axle of my '91 FJ80. The seal want bad and the complete axle housing was filled with sludge. I totally disassembled the axle and thouroughly cleaned it out, all new gaskets and seals, and refilled with AMSOIL grease and oil.
My problem is that the symptom I was trying to fix is still there. When I turn hard to the right or left and romp on the gas, there is a repetative clunking sound coming from the corner I am turning towards.
When I had the birfield out and degreased, I noticed that there was around 1/16" or 3/32" of movement if I pulled and pushed on the inner and outer axle.
How much play should there be in this joint?
If it is the birfield like I think it might be, should I replace it with OEM, or is there a profield or longfield for the FJ80s?

Greg Grimmius
'91 FJ80--ARB Bullbar, Jacobs Offroad Ignition

 

[Beowulf]

Greg,
It sounds like your PO waited too long for the axle service and your birfield joints are worn out. That sounds like too much play but I'm not sure what the tolerances are supposed to be. Maybe someone else can give us that information.

There are Longfields, Newfields, and Smurfs.... probably others. If your truck is a DD with a lot of off-roading which includes rock crawling then consider new OEM's. If your truck is mostly a trail rig then do some research on the xxx-fields. Your research should include an archive search here in the 80/100 section on IH8MUD. There are several posts discussing pros and cons of your birfield options.

-B-

 

[IdahoDoug]

Mine does that as well, and it's been well cared for. Interestingly, the repack with synthetic grease didn't really reduce the sound much. I attribute this to the balls simply being made more slippery and more easily sliding. However, I suspect they're now sliding easily and with less force because of the fresh lube. If you're just driving it on the road, have stock size tires and do some moderate wheeling I wouldn't worry about it. The 4.0 can't really generate a lot of force, either so....

That does seem like a lot of longitudinal movement - might have been a good idea to replace the birfield circlip as I *think* that's where this movement comes from. Anyone? Beuler?

DougM

 

[landtoy80]

How did the race for the balls look?
Could you feel a grove?
I had a grove where the ball wore into the race. I got new Newfields.

 

[semlin]

well I just had the same problem after a repack with a switch to redline grease. I had occasional single or double popping on very tight turns before but it actually got progressively worse afterwards for about 3 weeks although it seems to have levelled out now. Any moderately aggressive left turn yields half a dozen clunk/pops, while a hard right turn yields slightly less. I am 90% sure it is the DS birf. The birfield on that side was rebuilt 8 months ago after it went dry and broke (long boring story). They ground the bowl and used oversized balls. When I pulled it and repacked 6 weeks ago during the repack I noticed that the DS birf was much stiffer to pivot than the PS although it was still smooth and did not seem to hang up. I don't remember any noticable back and forth play on either birfield and I did compare the two because of the stiffness on the DS.

Anyway I do go offroad now and then and I don't like the progression of noise, so my solution is to replace. I don't like any of the aftermarket options and I really don't like the OEM price. FYI, there is a made in Japan aftermarket sold by manafre but Landtoy bought one last year and the abs sensor ring wouldn't fit.

After much thought I am going to try a used OEM that I am getting hardened by smurfield. If you can find a low mileage wreck I think this is the best route. Travis will check it out when he has it apart. If there is an apparent problem I might get it rebuilt by a different shop.

 

[Scamper]

I don't know what the factory spec call for, but when I did my axle, there was virtually no play in the birf--ran smooth as silk after repacking with snythetic.

Tom

 

[malcolm]

Toward the end of the knuckle job you bolt the spindle onto the knuckle housing, put on the hub, and then put the splined cap on the end of the propeller shaft (don't know name but recall the cone washers). Then you pull the shaft out all the way and put a snap ring on the shaft just outside of the splined part. My point is the propeller shaft is held radially at two points: the bronze spindle bushing and at the outside spline.

Normally when the wheels are straight ahead, the propeller shafts are spinning and stabilizing themselves like gyros, but when you turn the wheel, a kink is placed into the shaft and birfield, so it doesn't just rotate about its own center axis. Therefore, something is required to hold it in place otherwise it would tend to whip around. This radial location is accomplished by the spindle bushing.

My theory is that if you have noise when turning it's the birfield banging against the spindle bushing and the noise is not coming from the balls in the birfield. The shaft would bang because the ID of the spindle bushing has been worn out. I think it wears so bad because it is separated from the rest of the knuckle and doesn't get lubrication. .

I also think that people tend to grease the birfs well, but tend to neglect the spindle bushing. In fact, if you lube your birfs through the fill hole in the top of the knuckle grease will not get to the spindle bushings and they will dry out. Recall that when you install the snap ring you pull the shaft hard up against something? You were pulling the birf up against the spindle bushing. Grease can not flow through that flush fit. When the bushings dry out the shaft will grab and twist them in the spindle. I had to replace one of mine (Toyota upgraded the spindle bushings to a bearing).

I was thinking that to keep my bushings lubed I could take the splined cap off and somehow push grease inward along the shaft to keep the bushings wet. Haven't got that far yet though. The best solution would be to have a small hole the center of the shaft that would carry grease from the outside (like from a temp zirt) to the bushing area.

Everyone on here has had birfield experiences so don't feel you're the only one.

 

[80Diff]

Here's my answers to the responses:

Beowulf,
I bought the truck ('91) in '93 with 30,000 miles on it. any neglect to the axles was due to me. I did keep the bearings greased but that's as far in as I've gone. It is a 60% on road--20% semi challenging wheeling, and 20% hunting(logging roads) rig.

IdahoDoug
I am running stock 31x10.5s. Only mod to engine were 2.5" exhaust and Jacobs Ignition--minor gains in power. I did not pull the joint apart even though I had new clips available.
By the way, Coeur d'Alene huh? I'm at Mountain Home AFB. Have a friend from up there, does the name Rauenhorst sound familiar?

Landtoy80
I didn't tear the birfs completely apart. The balls looked good from the outside (no flat spots or pits). Guess I learned my lesson.

semlin,
Are those aftermarket birfs from manefre strong? I don't have ABS.

Malcolm,
I looked at the brass bushing and it didn't seem to have any wear at all. Might have been an illusion. Just goes to show that if you go deep into any project, buy all the little odds and ends so you don't have to go through what I am now. What you say makes sense. Except for the ends, the whole axle is floating within the housing and knuckle. I might just take the little cap off, run a bolt into the threaded end of the axle, and see how much up and down movement I get. Next time I open the knuckle up, I will replace and grease the brass bushing.

Greg

 

[semlin]

Greg, if you have no ABS then there is a regular supplier aftermarket birf available for only $100. Check this thread

https://forum.ih8mud.com/index.php?board=2;action=display;threadid=7479;start=msg63240#msg63240

Malcolm
worn bushings has got to be a symptom not the disease? Any contact between axle and bushing would surely only occur because there is too much play in the birfield.

Also, Landtank just went through a problem with spindle bushing contacting birfield. The result was a loud sustained screeching noise, not a clunking.

I want to believe you but you have to convince me!

 

[landtoy80]

I had the MAF birfields and I was not impressed with them even before the ABS ring didn't fit.
Pass on them.

 

[robbie]

It really sounds like you get to do it again. with no grease in the birfield you more than likely have the grooves that you did not see and this is the poping you hear. As the ball travels through the grooves. If real deep grooves you either need to have it repaired or replace. The stock one are about the best you can buy for the dollar. New fields suck and can create more havoc in the knuckle when they explode. As for Bobbielong treatment, great for hardcore but will wear out quickly as the treatment softens up the metal. later robbie

 

[PHAEDRUS]

I had mine remanned when I pulled mine out for knuckle servicing last spring. still running strong 20k later and no issues. used a place called cv axle express in Salt Lake City(lived ther then) how I found them was the fun part, called my local stealer ( No offense cujodan ) and asked the parts manager who they sent out birfs to to get remaned he gave me their name.
at 125 a side was not cheap but seems to be holding up fine in my rig.
Dave