700r4 - Downey - SOA (1 Viewer)

[walken100]

I've be im'ing folks on this topic for a while and I've decided to go public so you can share in my pain (or get a good giggle.)

After reading threads for hours and it appears that doing a spring over with a 700R4/Downey kit/LC transfercase is a not a "doable" deal but I'm going to try anyway.

I have a few different approaches I'm going to try and need some info. Lets start with driveshaft angle on a springover. What is the approximate driveshaft angle on a spring over with a 700R4. I know it will vary but I need a starting point.

For background the Downey kit uses a 1210 series ujoint to clear the trans. Turns out that there is a 1210 series double cardan joint. I'm thinking that using the cardan will allow me to rotate the pinion reducing the shaft angle enough to be usable at higher speeds (ie 55 mph on a snowy road).

So give me some angles and easy on the flaming please. Next option after I run this to ground.

Thnks for the help.

Bart

 

[TCinVA]

I had no trouble clearing the tranny with a springover with my 40 . I flipped the rear springs and the pinion stayed at a stock angle. I shortened my stock rear driveshaft and no vibration or clearance problems. I (obviously) lengthened my stock front driveshaft, had a problem with a flange not related to the truck so it isn't installed yet, but it clears just fine.

 

[walken100]

I had no trouble clearing the tranny with a springover with my 40 . I flipped the rear springs and the pinion stayed at a stock angle. I shortened my stock rear driveshaft and no vibration or clearance problems. I (obviously) lengthened my stock front driveshaft, had a problem with a flange not related to the truck so it isn't installed yet, but it clears just fine.

If this is the cruiser with the toybox you wouldn't have the same clearance issue as I have. the clearance I have won't even allow for a stock U-joint.

Your length is different enough that I don't think your angle measurements would relate to mine.

 

[TCinVA]

I see what you are saying, I didn't think about that. How thick is the adapter? The toybox is around 8" or so.

 

[walken100]

I see what you are saying, I didn't think about that. How thick is the adapter? The toybox is around 8" or so.

'

1". Front outlet snout is in contact with the 7004r Pan. However I now have an option to solve the problem if I cant find an alternative..... Add a toybox. Does the toybox bolt directly to the 700r4?

 

[TCinVA]

Yes, mine acts as the adapter. I ordered it directly from Marlin. They were hard to get on the phone, but once I did they were extremely helpful.

 

[walken100]

Any know the angle on there front driveshaft in a spring over? Need some examples.

 

[reddingcruiser]

I had no problems with the 700R4 Downey adapter and a SOA set-up. I did do a little (very little) clearance work in the u-joint flange just to make myself feel better. I do not have a double cardon. Some of these issues have to do with the angle the motor/trans is set up in relation to the frame - the lower the t-case is in relation to the front of the motor the more problems you have with the front drive line. I used a 1/2" spacer on the body mounts to allow me to raise the t-case without cutting the floor pan.
With an FJ60 front drive shaft in the rear. I left the springs in their stock configuration and rotated the the pinion up. Clearance around the trans pan for the u-joint is a pain but was fixed with a little sheet metal and TIG work. You also need a "pan-head bolt" or grind down the bolt head on the pan bolt that is directly in line with the driveline flange. If you really need it, I could measure my diff angles.
One thing I didn't do, but considered, was re-indexing the Downey adapter a few degrees to drop the . I don't think you would gain much for the extra work, though.

 

[reddingcruiser]

There are some pics of my set-up a page or two back under allands55 post "Transfer case shifter".

 

[walken100]

I had no problems with the 700R4 Downey adapter and a SOA set-up. I did do a little (very little) clearance work in the u-joint flange just to make myself feel better. I do not have a double cardon. Some of these issues have to do with the angle the motor/trans is set up in relation to the frame - the lower the t-case is in relation to the front of the motor the more problems you have with the front drive line. I used a 1/2" spacer on the body mounts to allow me to raise the t-case without cutting the floor pan.
With an FJ60 front drive shaft in the rear. I left the springs in their stock configuration and rotated the the pinion up. Clearance around the trans pan for the u-joint is a pain but was fixed with a little sheet metal and TIG work. You also need a "pan-head bolt" or grind down the bolt head on the pan bolt that is directly in line with the driveline flange. If you really need it, I could measure my diff angles.
One thing I didn't do, but considered, was re-indexing the Downey adapter a few degrees to drop the . I don't think you would gain much for the extra work, though.

Can you drive at speed without vibration in 4wheel drive? Are you using the small u-joint?

Funny, I spent the afternoon doing some measurments. 15 degrees of rotation on the transfer case = 1" of clearance which should be more than enough for the larger double cardan joint. Getting ready to pull the body off to put it to the test.

 

[reddingcruiser]

Yes, I am using the small u-joint and I do not have trouble with vibration at speed. However, let me know how it goes because I think getting the double cardan joint to fit would be a plus.

 

[walken100]

Ok, mocked up a transfer case rotation using the Downey adapter. Looks like 16 degrees of rotation will let me use a larger double cardan (or just a large u-joint). I give up 1.5" of ground clearance relative to the production location. But with the SOA and larger tires I'm 2-3 inches to the positive.

Adapter is at the machine shop being modified.

To be determined if it works but looks promising.

 

[srgould41]

I didn't realize you had clocked the tcse down like that. Should leave some room for the DC. Will you have enough ground clearance?

 

[walken100]

I didn't realize you had clocked the tcse down like that. Should leave some room for the DC. Will you have enough ground clearance?

Yes.... for me. Everything is a trade off and for me the ability to drive at speed in 4 wheel drive is important so I want a good drive shaft. Looks like ~1.5" loss of clearance relative to stock clocking. However I more than make up for that with the SOA and tires.

This is a work in progress so this hasn't worked yet. Off to the machine shop to pick up parts now. We will see.

 

[reddingcruiser]

Did you try putting the pan on, and is the accumulator installed the transmission? I saw those two items as the biggest problem in clocking the t-case.

 

[walken100]

ok, time for help. As you can see from the pictures I've had to clearance the pan (as planned). The good news is I'll miss the accumulator (again as planned) but I'm deeper into the pan than I wanted (not as planned).

So anyone know their poopy on a 700R4. Will this work? I've mocked up a pan that will clear a standard LC u-joint. I've lost 3/4" of clearance off the bottom in about 2" from the edge. I can tighten that up but this works well for shaft clearance.

On more not so important question. Do I need the slinger/cover in the third picture?

Thoughts, bets, "told you so" comments or just some help please.

 

[srgould41]

I clearanced my pan with a hammer Looks ugly, but it works.

 

[65swb45]

On more not so important question. Do I need the slinger/cover in the third picture?

Thoughts, bets, "told you so" comments or just some help please.

Thot#1. I wouldn't so much time and effort trying to re-use the stock LC shafts when there are 'easier' choices out there.

Thot #2. The front output bearing on the t-case is not s super-strong bearing for the job it has to do IMO, and driveline vibration in 4wd, even with brand new bearings is not uncommon. With that in mind, the dust shield becomes even more important to the life expectancy of the seal.

Best

Mark A.

 

[walken100]

Thot#1. I wouldn't so much time and effort trying to re-use the stock LC shafts when there are 'easier' choices out there.

Thot #2. The front output bearing on the t-case is not s super-strong bearing for the job it has to do IMO, and driveline vibration in 4wd, even with brand new bearings is not uncommon. With that in mind, the dust shield becomes even more important to the life expectancy of the seal.

Best

Mark A.

Not trying to use the stock shafts just using them for fit up and examples. I'm trying to get to a double cardan. Hopefully that helps with your second point which is good to know! I think I have room for the dust shield at this point. I also have room for a larger U-joint but not sure about the double cardan.

Thanks!

 

[bsilva132]

I don't see why it wouldn't work. If you add a trans cooler you should gain back (or even increase) the amount of fluid capacity that is lost due to the clearanced pan. Try PMing OrangeFJ45, he is an auto trans guru.