Hello, I will during one of the upcoming weekends replace my leaking differential seals. I've ordered the seals and the seal tool from Superformance. Do I need to remove the drive shafts completely to change the seals or can I just remove them on the diff side and push them away for access? The seal seating tool (Hill engineering): I understand that I will use the bolt that goes into the diff to press the seal inside, bit what does the bolt that goes into the sides of the seal tool do? Perhaps this will be obvious once I'm in there but for now it doesn't make fully sense to me. Thanks in advance.
You might be able to do the job with the one end removed, but experience has taught me to just remove stuff that will be in the way. You will spend a lot of time trying to work around not removing 12 bolts. Also, the seals should be directional, check and make sure the right one goes in the right side and the left in the left.
I don't know if it's possible to do it without removing the drive shaft, but I certainly wouldn't try it. Do yourself a favor and pull them off.
Just take off the driveshafts, the outboard bolts are easy to get at, so not much extra work. The seal tool bolt is just shown sideways in the picture of the tool, it is just a way to retain the bolt when in storage so you don't loose it. The way it works is the bolt simply goes through a hole in the centre of the tool, into the hub and you tighten the bolt to allow the aluminum part to press the seal in. It works beautifully, real easy. The job is not so bad, assuming the differential side bolts come off without trouble. I used the breaker bars and got a new allen key socket, made sure there was no crud in the bolts to prevent the allen socket from setting in well, and off they came. Those bolts are high torque. You should be aware the new seals might still weep a bit, the differential hub surface which the seal rides on would wear slightly over time. Or it might seal fine, depends on the seal and the wear and how things mate up. Some suggest the seal insert depth be ever so slightly different than what is specified to allow the seal to ride on a fresh surface. But I did mine to spec, and do have some weep. My seals were also from Superformance, but I don't blame the seal, although it is possible some seals are better or more flexible than others.
Thanks for all your replies. I will remove the driveshafts completely and now it makes sense with the seal seating tool.
A note since you are going to remove the driveshafts completely - remove (or at least loosen) the diff side first. If you remove the brake side first you have nothing to stop rotation and those bolts are known to be really tight.
Or you could just remove the diff side, see if the job can be done and report back. If it can't be done it's not like you have to go back and undo any work, just continue on removing the hub end.
From what I remember, the seals are not left and right sided. The ones I got from Superformance had an external dust seal that would ride on the rough part of the flange so I got some viton seals from a bearing shop. If yours look like the dust seal may not ride on the smooth surface, cut off the dust seal as the drag will deform the sealing lip. As others have said, get all the crud out of the cap screws!
Is there not a seal supplier that provides the factory correct seal without having to modify the part?
Oh yeah, I forgot about that part. Not only dirt from 35 years, but also possible to have that undercoat junk in there. Get it all out and make sure the tool is bottomed in the bolt head. Tap it in with a hammer to be sure. More than likely a 4" L key isn't going to get it done, at least not without a piece of pipe on the end.
Do you have any more information on the Daemar seals ? Sent from my iPad using FerrariChat.com mobile app
Not at hand but a decent bearing shop should be able to get them for you. Take the old ones or the measurements.
