720 IFS conversion to D21 front cv shafts

[HRH]

So I'm having a really hard time on availability for 80-82 720 4x4s for the front cv shafts. Can't find them at NAPA, can't find them through our competitors. I can have them rebuilt, but I'm wondering if any of you guys have tried the D21?

 

What I'm thinking is gettting the D21 front diff with extension housing and cvs and grafting that into the 720. Has anyone tried that, and what all would need to be switched on the hub side? I'm thinking perhaps you could use the full early D21 4x4 knuckle, but maybe with the extension housing the D21 shafts would go right into the 81 hubs?

 

Anybody try, have any ideas on this? I could also do the solid front axle swap, but am not going to due to time and money. I figure making the IFS work will be a little bit cheaper and easier. Any info would be appreciated. I may have to spend the off day over here on the computer looking stuff up.

[HRH]

Okay, checking out Schmuck's website since they happen to have an interchange built in on theirs and I'm not at work, I found this information:

 

Lower 4x4 4 cyl ball joint fits 83 to 94 720/D21

Upper 4x4 4 cyl ball joint fits 78 to 97 620/720/D21

 

So I would need an 83 or newer lower control arm from a 4x4 4cyl 720 or D21 to work with the other lower balljoint.

 

If those are both the same, I'm guessing the physical hubs would be the same.

 

On further review, the inner and out bearings and wheel seals fit the 83-94 4x4 4 cyl 720/D21 year range.

 

So that makes me think the only other options are rotor size, and placement of the differential considering the D21 has an extension housing, whereas the 720s just had the long shaft/short shaft setup. D21s are equal length.

 

EDIT: Lower control arm bushings may be different size from 720 to D21, not sure yet.

Edited February 9, 2009 by HRH

[tdaaj]

i'd like to hear the results on this.

[72240z]

I'm 99% sure the shafts in the cvs are interchangeable between the 2 so I would say splicing them together would solve the prob no?

 

If you need any physical info you cant find let me know, I'll hop under mine. Actually had it on stands today to hit up the grease fittings.

[Icehouse]

I've taken a few CV's apart and they pretty simple. So the only problem is the hub connection? Sounds like someone needs to take a trip to pick a part with a note pad :D

[HRH]

Well, it's a weird flange on the early 720 axles where it bolts to the differential, I think that's one of the differences. The late 720 axles can be found, but are also a pain in the ass. Seeing as hardbodys kept going until 97, they're easy to come by.

 

I might be able to salvage the boot, but looking at the other option, it would be much nicer to have an extension housing and equal length shafts to eliminate the tendency to pick one side up front.

 

Icehouse: I haven't taken a cv apart yet, I'm assuming they have little half ring clips kinda like u-joints holding them in?

[72240z]

I know you didn't ask me but I'm here so lol......They are called snap rings or circlips and ya that's what they use. Its very strait forward.

 

Here is a hbz thread to give you some insight.

forums.hybridz.org/showthread.php?p=899368[/url]

Edited February 10, 2009 by 72240z

[HRH]

Sweet, I kinda figured, just never had a need to rebuild one until now. And the 510 of course are u-joint. Done a million u-joints.

[HRH]

Did some scouting today. Yeah, not going to work. Not even close. The frame is radically different being the early 720 4x4 is more like an altered 2wd, whereas the later looks much more beefy and waaaay different on control arms.

 

In short, it would be easier to convert to a solid axle front. So, that means I'll try to repair the cv shaft tomorrow, and since I can't get an out boot, I'll probably use duct tape for the moment, though I'm not sure it's ripped, it may just be twisted.

[HRH]

I can't believe I'm even asking this question, but has anyone tried (*shudder) Autozone for halfshafts? I went online and they had part numbers for a Duralast cv shaft for right and left side for 1981 720s. Too late to call now, might be like Schucks where they have it online but can't actually get it.

 

I'm going to check tomorrow. I HATE supporting Autozone, but if they can get them, that's where I'm going to go. Of course then I'll have to deal with retards and a 90% chance of the part being wrong or really crappily made, but we shall see.

[72240z]

I got a set there to fix an acquaintances celica but I don't recall the brand. They were alright, and have been so far. I really dislike autozone but sometimes they are alright. Advanced and napa wanted like $140 for an ignitor for my d21 and autozone had it for $100 WITH a warranty. The warranty is imp because I had already bought one at aadvanced and it died a month later, had to eat it.

[HRH]

Yeah, I'm not a fan of Autzone, but considering I've checked Cardone who supplies NAPA and Carquest for instance, and they're on RR only, and Motion can't get them, basically all the decent parts stores don't have a listing for them. So maybe Autozone got lucky enough to pick up what the others didn't carry. Then again, it could just be wishful thinking seeing as I'm having such a pain in the ass trying to find the parts.

[HRH]

That's a big negative for Autozone too. So I'm back to square one. Looks like I'm going to repair the boot.

[72240z]

Did you check the link? Its actually a boot replacement write up I believe :-).

[HRH]

Link? I called them this morning, they have the part number like everyone else, it's just not available.

[72240z]

Post #7 there is the url of a cv boot replacement write up from hbz. Idk why the link didn't take, just copy/paste it.

[420n620]

Post #7 there is the url of a cv boot replacement write up from hbz. Idk why the link didn't take, just copy/paste it.

 

you just had to much to the link,,, here V

 

http://forums.hybridz.org/showthread.php?p=899368