Buggy Build Rear Steer Stupidity Check

[Ghetto Fab.]

Ok, I need a stupidity check. Is it a dumb idea to build a high pinion ball joint rear steer axle?

I've been wheeling my jeep buggy for about 10yrs now I think. Its time for refresh and I want more performance. I really want to make the new version rear steer. Problem is I have a champaign and caviar wheeling tastes on a beer and top ramen budget. I also don't see the point in taking out a second mortgage for something that only gets out once a year. I want to build a new chassis and try to reuse as much old stuff or the stuff I have lying around. Unfortunately I don't have LSs, spider nines or portal axles kicking around.

Current buggy has a low pinion gm kingpin front and low pinion 70hd rear.

I have 99-04 superduty outers sitting on the shop floor, along with some ford high pinion 60 front axle housing with no outers.

Option 1: Would be to use the high pinion front housing with the super duty outers to make a high pinion ball joint rear steer axle. I could offset the diff to the pass side to get both diffs on the same side. This would help get the rear driveshaft out of the rocks.

Option 2: Cut up the 70hd and put the super duty outers on that axle. Could be centered, or depending offset somewhat.

Seems like option 1 makes some sense, but I think I'd rather have the high pinion in the front and the low pinion in the rear. If I kept the low pinions front and rear though I could drop down to 6:17 gears which might be nice, but the 70 diff is huge. If you had one set of kingpin knuckles and one set of BJ knuckles, which would you put in the front vs the rear and why?

Scrap it all and buy a boat?

 

[SHARPMACHINE]

Yes, scrap it all. I pay scrap x2. I will have it picked up... lol


You are welcome.

 

[YotaAtieToo]

Hp 60 in the rear is obviously not great for anything but a mild rig.

Like you said 70hd is giant, adapting 4" tubes might be a pain also.

I like the e250 D60 rear as a donor. It's already offset to the pass side if you want to go that route. Has a nice smooth bottom and more clearance than any D60. The semi float version is usually pretty cheap and plentiful.

 

[Bebop]

Option 2 all day.

Option 1 is retarded and option 2 makes a little bit of sense.

Just add ball joints eliminators and you're in business.

 

[RPS1030]

I’ve got Chevy Kingpin 60 and Shaved 14 Bolt in the rig now. And a 05+ 60 already sitting around.

My 2 options are Fab 9 housing and the 05+ Knuckles to start trimming some weight, or use the 14 bolt.

 

[Ghetto Fab.]

I guess I should add that its just a basic do it all wheeling rig. Its not a racecar, comp buggy, or hill killer. It never sees highway time. Originally built to camp out of in the sierras, then I started going to JV, and now to sand hollow. I wheel pretty easy and have yet to break anything. Its got basically stock D60 front shafts with 35spline stubs, and worse is the D20 t-case with tera-low gears and the 10spline front output. I don't do front digs with it. I'd like to change that.

My point is that I'm fairly easy on things and I think a hp60 rear would do ok with my driving style. I know its not ideal though, and the ability to go to deeper gearing with the low pinion stuff is appealing.

 

[Ghetto Fab.]

Option 2 all day.

Option 1 is retarded and option 2 makes a little bit of sense.

Just add ball joints eliminators and you're in business.

Forgot about the BJ eliminators. That would solve that issue. Edit: If thats even an issue.

 

[Bebop]

Edit: If thats even an issue.

It is

 

[YotaAtieToo]

I guess I should add that its just a basic do it all wheeling rig. Its not a racecar, comp buggy, or hill killer. It never sees highway time. Originally built to camp out of in the sierras, then I started going to JV, and now to sand hollow. I wheel pretty easy and have yet to break anything. Its got basically stock D60 front shafts with 35spline stubs, and worse is the D20 t-case with tera-low gears and the 10spline front output. I don't do front digs with it. I'd like to change that.

My point is that I'm fairly easy on things and I think a hp60 rear would do ok with my driving style. I know its not ideal though, and the ability to go to deeper gearing with the low pinion stuff is appealing.

If you think HP rear would work, I'd be tempted to sell the current axles and just go with 99-04 stuff front and rear. Spend your effort retubing the front and leave the rear alone?

I'd anticipate needing beefier shafts and joints in the back though. Especially at sand hollow where you're sitting on your rear axle 80% of the time

 

[Ghetto Fab.]

If you think HP rear would work, I'd be tempted to sell the current axles and just go with 99-04 stuff front and rear. Spend your effort retubing the front and leave the rear alone?

I'd anticipate needing beefier shafts and joints in the back though. Especially at sand hollow where you're sitting on your rear axle 80% of the time

Yeah, the 1550 sized shafts would be nice. Of course now we're going down the path of things I don't have. I guess I have my doubts about being able to sell off the old axles for close to enough to buy two fronts, but that is a good option.

 

[94toytruck]

Had a similar discussion with a friend awhile back. He had a LP KP60 and a HP KP60. I suggested moving the LP KP60 to the back and putting the HP in front. Puts both diffs on the same side and their strongest position moving forward.

 

[YotaAtieToo]

Yeah, the 1550 sized shafts would be nice. Of course now we're going down the path of things I don't have. I guess I have my doubts about being able to sell off the old axles for close to enough to buy two fronts, but that is a good option.

I'm saying to use the current ball joint stuff you have plus pick up another. Personally, I'd hate to have rear steer with no common parts between the front.

Those pass drop king pin axles are gold! They will fetch $2k stock in norcal

 

[Wuz-A-zuk]

Option #3- use 70hd center, retube with 4" .375 (3/8") wall tubing. Machine tube I.D. out to 3.5" and just slide C's in and weld.

Sounds like a lot of work compared to your other options until you consider not having to do anything to the "C" but just having to cut axle housing with however much press in tube you'd like. Also save you weight being thinner wall and lets you put the diff wherever you'd like.

Unless I'm missing something, literally just came up with this while reading the thread.

 

[Ghetto Fab.]

Had a similar discussion with a friend awhile back. He had a LP KP60 and a HP KP60. I suggested moving the LP KP60 to the back and putting the HP in front. Puts both diffs on the same side and their strongest position moving forward.

I had similar thoughts, but the current t-cases I have are all pass drop.

 

[Ghetto Fab.]

Option #3- use 70hd center, retube with 4" .375 (3/8") wall tubing. Machine tube I.D. out to 3.5" and just slide C's in and weld.

Sounds like a lot of work compared to your other options until you consider not having to do anything to the "C" but just having to cut axle housing with however much press in tube you'd like. Also save you weight being thinner wall and lets you put the diff wherever you'd like.

Unless I'm missing something, literally just came up with this while reading the thread.

That was basically option #2. I can't remember the wall thickness on the 70hd, but it is 4" tubes. I'd most likely look at some means of turning down the 3.5" tubes to fit in the 4" tubes.

 

[Wuz-A-zuk]

Agreed, I was just adding that running a smaller tube thickness (I believe it's currently .5 wall) and "retubing" it lets you save some weight and put the diff where you wanted basically cancelling out most of the pros of option #1.

Basically with this method the only thing "option 1" has is HP which I wouldn't necessarily call a "pro" for rear use depending on power plant.

 

[Ghetto Fab.]

It sounds like, while these ideas might work, none of these scenarios are ideal. I guess I need to decide if I want to look at other options and tear this thing apart or just park it till next years trip.

 

[Bebop]

Ideal options will involve more money.

 

[YotaAtieToo]

I think if you priced Dom tune that size, you'd rethink that option

Personally, That 70hd is just so huge, I wouldn't waste any time on it. Rear axles are cheap enough to just pick whatever donor you want.

 

[Ghetto Fab.]

That's sorta where I'm starting to go. Retubing seems difficult. If I could just machine what I have to make things work that would be easiest. Honestly selling off what I have and getting into something thats better with more options might be the way to go. I keep thinking about building a set of 609s. I could build a 609 with the outers I already have for the front. Sell the set of axles I have, then find another superduty axle and build another for the rear. More dollars, but more ground clearance, more gear ratios, and I could go high pinion in the future.

I think this is one of the reasons I keep putting this off. I need to change so much of this thing for any upgrade to make sense.

Any thoughts on dragging low pinion nines through the rocks?

 

[Ghetto Fab.]

Any thoughts on dragging low pinion nines through the rocks?

Bringing this back from the dead. Any thoughts on dragging low pinion 9s through the rocks? Just run a cv driveshaft and rotate the pinion up? Or, no need to worry? I don't have monies for gearworks bling.

 

[TanTJJim]

Bringing this back from the dead. Any thoughts on dragging low pinion 9s through the rocks? Just run a cv driveshaft and rotate the pinion up? Or, no need to worry? I don't have monies for gearworks bling.

If your previous point of reference was dragging a Dana 70 through rocks, dragging a low pinion 9 through rocks will feel like throwing a hotdog down a hallway

I'd put a pinion guard on it, point the pinion up and hammer down! (Personally I'd do the same but with a shaved 14 bolt bolt but maybe you want to run with what you have)

 

[94toytruck]

I cut the pinion guard off my 14b. Did more harm than good, it would hook stuff and stop me dead even rotated up some. Those things don't exactly sit close to the driveshaft. Run a round flange instead of a yoke and leave the pinion guard off.

I actually plan on replacing my 14b with a low pinion 9 eventually. A HP in back would be awesome but it's not in the cards.

 

[Sean]

Bringing this back from the dead. Any thoughts on dragging low pinion 9s through the rocks? Just run a cv driveshaft and rotate the pinion up? Or, no need to worry? I don't have monies for gearworks bling.

IMO, LP 9s suck in terms of driveshaft clearance....so bad, I personally wouldn't run one. If I was trying to keep it cheap for a 3rd like that, I'd probably go with a LC 9.5" instead (though I wonder if the misnamed Toy 8.4" with the girdle might be better). Too bad 10.5 Tundras aren't cheap/plentiful with lots of locker choices.

 

[Ghetto Fab.]

IMO, LP 9s suck in terms of driveshaft clearance....so bad, I personally wouldn't run one. If I was trying to keep it cheap for a 3rd like that, I'd probably go with a LC 9.5" instead (though I wonder if the misnamed Toy 8.4" with the girdle might be better). Too bad 10.5 Tundras aren't cheap/plentiful with lots of locker choices.

I considered the LC9.5, but I think you can only go to 33spline shafts in those, if that? While the 70hd isn't bad, lighter weight, fabricated housing and a drop out 3rd all seem like benefits to me.

 

[Tech Tim]

I considered the LC9.5, but I think you can only go to 33spline shafts in those, if that?

You can make them the LC9.5 35 spline. If you have the newer 2 piece ARB, they have 35 side gears that drop right in. In you have an older 3 piece ARB, I still have 3 or 4 sets of 35 spline reboached side gears in the loft.

 

[Tydes]

my buggy’s has a Dana 70 with superduty outers in the back (rear engine, flipped diffs) and my wife runs low 9s front and rear. Either will do just fine. I like the 9”s for the deep gearing.

 

[YotaAtieToo]

my buggy’s has a Dana 70 with superduty outers in the back (rear engine, flipped diffs) and my wife runs low 9s front and rear. Either will do just fine. I like the 9”s for the deep gearing.

D70 goes to 7.17s also? Very close to the 9"

Unless you're referring to the massive selection of deep gearing, os some people claim the 9" is much stronger in the deeper gearing?



The 9.5" isn't bad for what it is, bit I believe it needs a load bolt to be strong. The carrier and ring gear design lead to more deflection that other similar sized difs.

 

[Tech Tim]

The 9.5" isn't bad for what it is, bit I believe it needs a load bolt to be strong. The carrier and ring gear design lead to more deflection that other similar sized difs.

The late model '98+ carriers and ring gears have the R.G. bolts go into the back of the gear like a standard ring gear. The pinion also has a larger splined section. iirc 27 to 29 spline.

I'm a fan of the 9.5" for Land Cruiser applications or those who want to stay Toyota. Beyond that, the 9"/10" platform has many more benefits.

It's too bad we can't get one of the bigger axle companies to come out with a Hi 9/10 3rd and supporting gear sets for the masses. Currie and Yukon would be the first to come to mind.

 

[Weasel]

Buddy just did the D70 with super duty outers for rear steer on his Twisted Buggy. It seems to work just fine.

Your already used to LP axles. Drop to the lower gear set is a good plus.