birf service question on shims (1 Viewer)

[sodajerk]

Has anyone else only had one adjusting shim on the top of the knuckle and none on the bottom? That is what I discovered. I did not have a fish scale to test but the knuckle did not seem overly tight.

What would the results or sysptoms of un overly tight knuckle bearing be?


Russell

 

[landtank]

on all the axles I've done that is how I found them. I just reassembled and moved on. A tight bearing would have a greater resistance to movement and give a higher reading on the scale.

 

[snowwolfwarrior]

Mine was the same here in the UK

 

[Lars]

Just another confirmation....

I serviced my birfs and knuckles last weekend. I encountered one shim on top, none on the bottom.

 

[dd113]

Thats common but remember if you are putting in new bearings the original shims are just a starting point and may or may not give you the required preload. If you are keeping the bearings then you should be fine but you need a fish scale either way for the wheel bearings and to check the knuckle bearings.

 

[landtank]

CDan replaced his axle but used his old knockle housings. After going through the proceedure he ended up with the same shim thickness as the old axle had. Todays manufacturing tollerances are so much better than before you don't need to worry about the fishscale thing with the trunions even if you replaced the bearings.

 

[dd113]

CDan replaced his axle but used his old knockle housings. After going through the proceedure he ended up with the same shim thickness as the old axle had. Todays manufacturing tollerances are so much better than before you don't need to worry about the fishscale thing with the trunions even if you replaced the bearings.

I can partially agree with you. 80 Series are much easier and "most" of the time the original shims will get you in the preload ballpark; but not all the time. Considering the amount of work involved to redo the job it seems like cheap insurance to buy a $10 scale.

 

[snowwolfwarrior]

but surely all the astiction is in the new rubber seal and felt, it does seem a bit hit and miss, you can torque up whell bearings to 54lbs feet, and still easily turn the hub by hand, or am I being a bit nieve and the preload is done before doing up the seal cover?

 

[landtank]

The big issue is what you are using for grease and at what temperature you're using it in. Synthetic grease is thicker than dino and as the temp drops the grease thickens. Too many variables that will give erratic results for this sort of proceedure to be taken seriously. More often than not people who follow this proceedure for the wheel bearings end up having isssues with loose bearings soon after, do a search. Now if you use the specified grease in the specified enviroment than it should work fine. Now find grease that doesn't exceed 10 year old viscosity ratings and a temp and huimidity controlled garage.

 

[T Y L E R]

Rick , what grease did you use on yours ? We have similar weather , though you drive your 80 a whole lot more than I . I need to quickly line up my last few ducks before I travel and do this axle service .

Thanx

PS : I'll put in the best there is ... as long as it is for my application , weather etc . And I'll be changing the difs back to 75W90 after the axle service (Mobil 1)

 

[cruiserdan]

80 series axles shim only from the top. There are no bottom shims.

 

[landtank]

Ty, I use high temp wheel bearing grease, dino variety. In side the birf I do use synthetic, moly fortified.

 

[LandCruiserPhil]

I had some time available to play when I did my last front axle service and found that for every .10 shim that was reduced I gained 1 pound in preload. With new bearings (greased) I had 6 pounds of pre load (5.6-9.9 spec.) when a .20 shim was removed I had 8 pound on a scale with 25 pound max. I would be interested in other results.

 

[dd113]

The big issue is what you are using for grease and at what temperature you're using it in. Synthetic grease is thicker than dino and as the temp drops the grease thickens. Too many variables that will give erratic results for this sort of proceedure to be taken seriously. More often than not people who follow this proceedure for the wheel bearings end up having isssues with loose bearings soon after, do a search. Now if you use the specified grease in the specified enviroment than it should work fine. Now find grease that doesn't exceed 10 year old viscosity ratings and a temp and huimidity controlled garage.

I just cant agree on this one. I have done over 30 sets of 80 series knuckles and on every one used the spring scale method and I have never had any issue with the knuckle bearings being too loose, once pre load is set correctly.

I will buy the arguement that the grease and outside temps could give you an artifically high reading; that is why there is a range of correct preload values. if you think you are getting an artifically high reading then take the preload to the higher end of the range.

If you do the wheel bearing according to the FSM with the initial lock down and turn procedure then set it to the hi end of the range I dont see how you can have loose bearings.

People who do this all the time can do it by feel. People that are new to it need a place to start and I think you could do much worse than to follow the FSM.