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Front drive shaft assembly alternatives for 1981 720 4x4?

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All my boots are shredded and my mechanic is telling me it will cost ~$900 to replace ONLY the boots. Normally he said he'd replace the whole assembly because it's actually cheaper to do that, and with a vehicle this old a wise move. However, there appear to be no new or emanufactured front drive shaft assemblies for this model anywhere on the entire planet. I love my truck but can't justify paying that much knowing I may need to replace a bearing or shaft soon and then have to pay for everything again.

So I need the advice of the real experts here. There are assemblies for 83 and later 4x4 models readily available but I have not heard back from any of the suppliers if they could work for an 81. My mechanic isn't that familiar with this model truck and has limited resourcefulness for suggesting alternatives here. (He has no suggestions other than the $900 boot only fix) If the 83 assemblies will work, problem solved. If not, what should I do? What would any of you do? Front end swap? 2 piece boot repair kits? Pick and pull? Everything currently works and my plan is to drive this truck until I croak. I seriously love everything about it. It is in incredible shape with no rust and I plan to line the bed and rustproof the body and frame (bought truck in Arizona but live in Ohio) soon but really want to resolve the boot issue first. I will not be doing any serious off-roading in this truck. I just like driving it. Sorry if this is too much info or not enough. I've searched the topic and can't find anything on this in existing posts. Apologies if I've missed anything there. I know there are geniuses on here that love this vehicle as much as I do and I need your help!

 

Thanks for your time!

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Sorry, just answered my question. Thought this was a vehicle term not a forum term. Thanks.

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Yeah new posters need mod review and approval. Your post would have been approved but might be burried so I brought it up. Sealik, a member on, here has some 720s and could advise what boots will fit or even if available. $900 is robbery. $50 each is more likely. I think the early drive shafts are no longer available, maybe later ones wil lfit.

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The 83+ halfshafts are of a different length...being that the diff is in a different position.....no workie

The 80s will work on the 81/82...just swap em....side to side,.... drivers side to passenger side, passenger side  to drivers side.

Again...that's because the diff is closer to one side of the truck than the other...also because of the L or Z motor used.

 

Just buy an FSM and a boot kit and do it yourself.....pretty easy. Boots(2) with grease are around 30 bucks per side

That said.....the 83+ halfshafts are easy to disassemble, being that just a circlip holds them together.

Not sure if the early ones needed to be press fitted though

 

Cvaxles_zpsdaef0750.jpg

 

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The 83+ halfshafts are of a different length...being that the diff is in a different position.....no workie

The 80s will work on the 81/82...just swap em....side to side,.... drivers side to passenger side, passenger side  to drivers side.

Again...that's because the diff is closer to one side of the truck than the other...also because of the L or Z motor used.

 

Just buy an FSM and a boot kit and do it yourself.....pretty easy. Boots(2) with grease are around 30 bucks per side

That said.....the 83+ halfshafts are easy to disassemble, being that just a circlip holds them together.

Not sure if the early ones needed to be press fitted though

 

Cvaxles_zpsdaef0750.jpg

Thank you for that information!  I'll check the FSM to see if I need a press.  I'd rather buy tools than time. Thanks again.

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Actually.....you might not need a press, just have to remove one of the joint/spider assemblies.
One side is pressed on...the other should slide right off.
Once an assembly is removed...clean them up, re-pack/add grease and install the boots.
I believe I had to buy extra CV grease..... was not enough supplied in the kit.
160 grams/5.64 oz per boot.
Do not reuse any boot bands

 

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Thank's Doug.

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Thank you guys for helping me out here! Think I've gotten exactly what I needed to know. Mike, loved the story in your profile. Hope I can pay it forward someday!

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Actually.....you might not need a press, just have to remove one of the joint/spider assemblies.

One side is pressed on...the other should slide right off.

Once an assembly is removed...clean them up, re-pack/add grease and install the boots.

I believe I had to buy extra CV grease..... was not enough supplied in the kit.

160 grams/5.64 oz per boot.

Do not reuse any boot bands

Thank you Doug! I'll be tackling this next weekend.

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I used s13 Megan racing silicone cv boots on my 1980. The inner output shafts are triangle shaped like a 240sx so don't buy circular boots for the inside.outside is round so a normal boot will work. The spider bearing is pressed on and the other side is not removable or rebuildable. Mark the splines before removal to reindex the slider bearing.

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IMAG0201_zps0e41ab51.jpg

Thank you. Have the zip ties held up ok? I'm a little confused about the inner triangular boot comment. In the photo all the boots appear to be round. Are there boots inside those boots or am I simply confusing which aspect of the shape you are referring to? The link GGZILLA posted has inner and outer boots for this model year and I was just going to buy those. Would that work or am I missing something? Thanks for the post btw. I'm sure some things will be revealed when I start tearing things apart.

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The inner output shafts are triangle shaped like a 240sx so don't buy circular boots for the inside.outside is round so a normal boot will work. 

 

Good call nismofo....I forgot about that

 

 I'm a little confused about the inner triangular boot comment. In the photo all the boots appear to be round. Are there boots inside those boots or am I simply confusing which aspect of the shape you are referring to? The link GGZILLA posted has inner and outer boots for this model year and I was just going to buy those. Would that work or am I missing something? Thanks for the post btw. I'm sure some things will be revealed when I start tearing things apart.

 

 

Yes...the inner and outer boots have a different PN.

I'd ordered from a local auto parts dealer ....so I received the correct ones

Soon as you take it apart you'll see what 'we're' talking about.

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Zipties work fine, some cv boots come with zipties. The ones I used are larger around 7/16th of an inch,they are not going to fail anytime soon.

In the picture you will see at the farend of the driveaxle assembly the spider bearing housing has two concave sides. Their are three concave sides and three convex sides resulting in a somewhat triangle shape.

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Zipties work fine, some cv boots come with zipties. The ones I used are larger around 7/16th of an inch,they are not going to fail anytime soon.

In the picture you will see at the farend of the driveaxle assembly the spider bearing housing has two concave sides. Their are three concave sides and three convex sides resulting in a somewhat triangle shape.

 

Very cool.  Promise this will be my last question on this topic...have any of you ever used one of these air tools to replace a boot? 

The reason I ask is that I am a little concerned about the disassembly/separation of the driveaxle shafts from the assembly housings.  I don't have a lot of experience with this type of repair (none) and would be happy to spend the money on the tool if it can increase my chances of not screwing something up.  If on the other hand, the disassembly is a critical part of the cleaning and grease packing, I'd skip the tool.  Considering the scarcity of the new or re-manufactured assemblies I had to ask.  Thanks for the help!

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That cv boot tool is for a special fkexable boot called a dura boot. It's unlikely they have them for the triangle shaped cv boot needed for your inner constant velocity joint.

I picked up a 20 ton shop press from harbor freight for 150, probably cheaper than that tool.. you will need a press anyways just to do your front rotors and may as well do bearings races and seals. It's a huge pain in the ass but having a press around will save you money.

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And yes the Megan kit has the triangle boots for the inner abd outer. The outers will have to be modified to fit because of the triangle shape. You will need a sharp utility knife to remove the unneeded material that makes the triangle shape. This will make it circular to fit the round outer cv.

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That's pretty cool. Thanks. So it's ok to not disassemble the whole thing to repack with grease then?

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I'd be tempted to pull the shafts right out.....clean everything up....lube assemblies.....locate cone.........install boots....etc.

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