Flexx Boot Axle Repair Using Cone
 

Ok here it is. It was not as difficult as I imagined. As mentioned in a previous thread, the GSP axles I just put in were not any good:mad: and am not about to experiment and replace them with replacement GSPs since the job is not exactly a snap to do.:rolleyes:

So here's how I did the flex boot work.

First I unfastened the oe straps off the boots. Then I slid out the old boots from the can and poured the gear oil out of it (have a container handy for the used oil). Each axle end took about 1/2 pint since both axle assemblies took a total of 1 qt.

Then I sprayed the inside of each axle with brake cleaner. Afterwhich, I cleaned it off with compressed air and poured a few drops of oil back in to it just to keep it lubricated.

I did not cut out the old boots yet. I kept them in the shaft since I was not sure how well the manual flexx boot installation would go.

Next, the Flexx boot installation process.

Soaked flexx boot and cone in hot tap water for about 3 minutes
http://i158.photobucket.com/albums/t...r/DSCN1744.jpg

Used Pledge to spray cone and boots to ease sliding. I inverted the boot inside out.
http://i158.photobucket.com/albums/t...r/DSCN1745.jpg

Could not take pic of boot on cone since I was by myself but heres the boot already on the axle. I had the axle resting on the table on a vertical position. It took some effort but but not too bad. Used paper towel and rag to hold and pull boot down. As a precaution, note that I did not cut out the old boots until I was sure I could put in the new boots.
http://i158.photobucket.com/albums/t...r/DSCN1748.jpg

I had to try it 2X for each boot to slip thru. It pretty much pops right thru.
http://i158.photobucket.com/albums/t...r/DSCN1752.jpg

Another view
http://i158.photobucket.com/albums/t...r/DSCN1751.jpg

I inverted the boot right side out and cut the excess piece.
http://i158.photobucket.com/albums/t...r/DSCN1755.jpg

After removing the old boots, draining the old oil out, shoving in the new boots and correctly fitting the new boots (trimming unneeded rubber) on the axle, position the axle so it is standing standing upright on a work surface. Do not clamp the new boots yet. Push it out of the way. Get the large and small clamps ready.

With the axle upright, fill the lower axle with new oil. IIRC, it took 1/2 pint or up to about half an inch filled over the gear. Once filled, reposition the boots on the axle.

Install the large clamp and the small clamp. Do not overtighten so you won't tear the boot. This completes one end.

Repeat the procedure to do the other end. I recall that all 4 axle ends took a total of 1 qt.

http://i158.photobucket.com/albums/t...r/DSCN1756.jpg

Heres the boot installed, the old boot and the strap fastening tool. The rings around the shaft are part of the old boots. Each boot had a ring inside which kept the rubber boot round. I made sure that I fastened all the new straps to the new boots before cutting out the old boots.
http://i158.photobucket.com/albums/t...r/DSCN1761.jpg

Final product and the stuff I used.
http://i158.photobucket.com/albums/t...r/DSCN1765.jpg

All in all, it probably took me about an hour to do both axles. And thats taking my time doing it.:)

Yes, Henrietta, there is gear oil inside those cans. Now lets see how long they stay there.:)

Nice job documenting this process with pics! I haven't studied posts on the process but one of my axle's boots have what looks like deep cracks along the ridges. I should probably do this while I still can...

Thanks again for all of your write-ups recently - very helpful.

That's some good work. If the axles are in good condition, the cost to do that job is minimal as compared to getting replacements.

Where did you get that cone? Is it available online or from a McParts?

I got it from Astoria along with the boots, straps and tool. They were the ones who suggested soaking hot tap water and spraying pledge.

Edit/update:

I mentioned this on a later post but i ended removing the astoria boots and used Dorman boots instead. The astorias gave excess rubber accordioning which resulted into it getting pinched when reinstalling the axles. The Dormans are also a bit more sturdy. They did require more effort to slide in but not bad.

Since you'll never use the tool again, you might want to put it in the rental program..........or an ongoing sale program.

Or, you could give use that part numbar and price!

Flexx Boot 3000 (includes strap and grease) $17 each
Strap Fastener tool $20
Cone $20
http://www.astoria2000.com/

Valvoline Durablend 80W90 oil $6.99 AZ
Pledge $???


As far as I know, Fastlane does not sell the Flexx Boot.

Great job. Thanks for sharing.

Regarding the GSP axles, are you sure you used the correct size spacer? I think I read somewhere the GSP axles does not take the original spacers.

I too will be doing this soon....we'll see how it goes! :D

All I know is that the C clip went in fine so that tells me the spacer was ok.

Sounds right. If the spacer was too thick it'd not have gone in properly. I bet it was just a tolerance problem in the axles. Can't expect all that much considering the price.

Think we might be able to rent that cone and clamp-tool from you sometime soon? :D We still need to order the flexx boots and such, hopefully we'll get to it sometime in the next few weeks.

But if the spacers were too thin, the C clip would of also gone in fine. You would need to make sure the axles were seated in properly and check to make sure there was no gap between the C clip and carrier. Even a slight gap could wreak havoc in there.

Marz, no gap or play if thats what you meant. The clip actually went in snug.

There really isn't much to the whole process. Once the bolt from the wheel end and the C clip from the diff end are removed, everything slides out. So, I can't imagine what else would cause the "rubbing" or "clunk" sounds from the rear end.

pawosd, just let me know when you are ready to do it. We can work out something.

By "accordioning" did you mean the Boot was stretched too tight when installed or that the Boot was collasped too much?

Would not installing the clamp on the small end of the Boot until the Axle is Installed heip prevent it from getting pinched/damaged?

How would you keep all that oil from coming out?

I guess the key is to be super careful.....I just ordered 8 boots last night. :D And a bunch of other parts. We should be ready to do this on both cars by sometime next week!

I also need to do this. My axles are still good but the boots look aged.

How much grease should be put in the boots?

I think they are going to get a fair amount of business from this forum.

I'll be interested to see how the gear oil works out. It seems to me like it has the potential to leak out through the clamps too easily leaving the joint dry.

Using your terminology, collapsed to much or too much rubber bundling up.

I cut off the 1st section which was too big. The 2nd section is about 1/16" bigger all around and is I what used. The 3rd section would probably work but only if you stretch it around the can.

Anyway, here's where I'm at.

I removed the punctured Flexx boot (actually removed all of them) and tried the Dorman boot instead (from AZ). I like the Dorman better. It is actually a heavier boot and it fits the can better (after removing 2 sections). It also bundles up less.

As to the oil thing, I know I am taking a bit of risk here but my installation is no different than the OE as far as the clamp I am using and how the boot is clamped.

I will be keeping an eye - and ear - on the axles. If there will be any evidence of leakage, I will just pop the axle end of the boots and stuff grease in there and reclamp. The clamps are actually reusable if you remove them carefully.

I have to agree. I chose the Dorman boots instead of the Flexx boots on my Honda because it was thicker using the pneumatic Flexx (Snapon) gun.

I guess you could not keep the Oil from coming out; but, I thought most folks were using Grease.

Has anyone posted the Part Number for the Dorman Boots?

IMO, using gear oil in axle boots is asking for trouble. If it was better than grease, Mercedes and every other car manufacturer would use oil instead of grease. A century of engineering says use grease, not oil.

Who said the OE lubricant was grease? The OE lubricant is gear oil. Or at least thats what was in my OE axle.

Dorman 614 001 Universal Boot for both inner and outer.

Oil is OE, not Grease.

I tend to believe that M/B had some good reasons for using oil. The oil, if the boots are filled completely, will always be on the bearing surfaces. The grease will be flung to the outside of the boot, leaving the bearing surfaces without the desired lubrication, unless the boot is completely packed.

The longevity of these axles with the use of oil should give one pause before grease is selected for a replacement lube.

Exactly. I will be filling all of ours with oil when I redo them soon for this very reason.

We have a big pile of flexx boots coming in, hopefully they hold up ok, I'll have to be real careful.

I was not recommending Grease but mentioned Grease as I believe I read that some of the other Members have used Grease.
I have only had experience with 1 CV Joint on a 86 Chevy Cavalier with a ripped Boot. It had Grease in it when I cleaned it out and I re-packed it with Grease when I installed the split Boot and that was over 6 years ago.
All CV Joints that use Grease must fling the Grease yet they seem to work fine;with Grease engineered for the job.

Grease is great if you are out of town and the hole is not that big. Garrett helped me out by spooning it into my ripped CV with a sprok from taco bell. it worked for about 100 miles then another few sporks full got me home. (nothing like going to get your lady from the airport and having the axle start banging.... those were the days)

They make some very very nice grease these days. the grease we used in our make shift solution was marine grade and water resistant, and about a sticky as any glue I've used. we used it so it wouldn't fall out of the rip as fast a wheel bearing grease. after going grease shopping I might be up for doing some research before going with oil only because if the boot were to rip you wouldn't be dead in the water. (since the replacement boots are thiner) but since there are many different kinds of grease out there it would take some research. the safe bet is gear oil. but I bet there is better grease out there.

well, Ive never seen an axel boot filled with oil....

it seems to me that oil would be the better option because it provides constant lube.

I guess someone needs to take a survey of folks who have used Grease on there Mercedes CV Joints when the replaced the boots and see what type of reliability they achieved.

The differential + axles I removed from a 500SEL in the yard a week ago had oil in the boots. I accidentally dislodged one of them a bit when moving it around and some oil leaked out.

tobybul, where did you get the red funnel?
A few months ago, while collecting info, I bought a transmission funnel and a Dorman boot at Auto Zone. Took it to my Indy to prove it would work, and it didn't. I didn't warm the boot. I didn't know that trick. Have to try again.
Also, the boot came with a package of grease(oil?). I would rather use good stuff, but I guess the amount in that package is all you need in one boot. Measure contents and use the synthetic instead.

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1984 MB 300SD Turbo

I got the cone from Astoria when I ordered the Flexx Boots. It actually works pretty good. It is more important to warm the boots, especially the Dormans since they are thicker but I got them thru.

Its best to have 2 ppl pushing the boot thru the cone in tandem. It does require some effort but its very doable. I got the 4 Flexx boots thru by myself but only 2 of the Dormans until I asked by muscle-man son to help me out for the remaining 2.

And again, I opted to use oil instead of grease for the same reasons stated by others above. Its what MB used. Grease I'm sure will work but I would probably pack it with a lot more grease than the quantity that comes with the boots to ensure that the balls and spider arelubricated.

Also, I think the pinch type or also called SAE SEC clamps work better than the peel-back type that come with the Dormans. NAPA sells the pinch type. They also come with the Flexx boots. They can also be reused if you remove them carefully.

Dorman boots on OE axles
http://i158.photobucket.com/albums/t...l/DSCN1774.jpg

Dorman boots on OE axles
http://i158.photobucket.com/albums/t...l/DSCN1774.jpg[/QUOTE]

Is the boot on left a flexx? Looks kind of screwy.

All Dormans. THe rubber is just pushed in a bit since I just installed it. Might need the small end moved closer to the big end.

That should straighten up once you drive it for a few hundred miles.... But let us know if it does or does not. Then well make the necessary adjustments.

Flexx Boot Axle Repair Using Cone
 

Great write-up, and even better pictures!
I read it several times and found nothing to indicate where you got the 'cone' you used. I could not find anything at the 'astoria200' web site indicating that they had a 'cone' available.

So I guess the question is: "where did you get the cone?"

Farrell

I was looking too. I think you must phone them.


---------------------
1984 MB 300SD Turbo

I used the grease
 

I used the grease that came with the flex boot and some 90w gear oil ... have been running down the road for about 20k now ... no problems with the flexx boot , grease , and 90w gear oil ... let you guys know when they wear out could be a while..... mercedes uses oil for their half shafts by the way .... I used the Flexx boot pneumatic tool fast and easy to use ... anyway have fun

Sorry Ryan. I just saw your post. I don't think Astoria shows the cone online but if you call them they will sell you the cone. I think they prefer to sell their Flexx gun but they still have the cone if you ask them.

I wished I'd have used a combo of the grease and some gear oil. I went with the grease because the Astoria folks weren't sure the flexx boots would seal in the gear oil well enough.

We just used oil and it seems to be working fine....

Talked to the folks at CVJ axles and they confirmed that Mercedes in the past used heavy gear oil for their CV joints. But Mercedes have now switch to Grease because the technology of grease is better today. CVJ uses grease in their axles.

I started this job today. I got me a nice funnel and cut it to work, 4 new Dorman axle boots, and mobil 1 gear oil for the joints. I'll say this, those rubber boots don't stretch out quite as easy as other members said that did. I broke 2 boots. Anyways all 4 boots are on and I decided to call it night. Just need to fill them up with oil and then pu them back in. How did everyone else fill the boots will oil? I was just going to clamp the big end of the boot and then pry open the small end of the bott and fill it up with oil. Good idea, how did everyone else do it?

BTW, I think that MB filled the CV boots with tranny fluid, atleast that was it looked/smelled like. Im using gear oil though.