Build TDI-J70 - LJ70 TDI Swap (Erika)

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Well FML. Gears wouldn't fit through the opening on my HF press, I stacked 2x4s to press off the big gear and bearing which went just fine. Then went for the other side and was taking a ridiculous amount of pressure and kept splitting the wood. I had watched the OTRAMM split case video and seen him pressing them off directly on the press plates and assumed that was fine to do on these types of gears. What I wasn't aware of is he was probably using aluminum plates. Put it on my press plates and again took quite a lot of pressure till it completely exploded apart. Small gear now has chipped teeth. Guess I'm ordering 3:1 gears...

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This seems to be the kit I need. 3.1:1 keeps the 1:1 high range and minimal case clearancing. Don't want the 3.3:1 as that has a 1.1:1 high range, trying to keep highway RPMs down. Has 34 to 38mm conversion idler shaft and a new high speed gear which is the one I F'd up. I guess it will be nice to have a brand new split case to go with the brand new trans, but the money just keeps flushing down the toilet...

Any input before I pull the trigger in the morning? Or a sympathy discount code from @cruiseroutfit after having bought a rebuild kit too? 😢😂😭
(anyone need a new 34mm idler shaft and bearings?)

 
That's rough! Some of those splines take some serious force to get apart. Being a 1987 I would have thought you already have a 38mm idler shaft? Could you not get away with just the gears?
 
"Minimal clearancing" 😆

Weld something on there before machining. It's a bitch to fill a hole back in.
 
That's rough! Some of those splines take some serious force to get apart. Being a 1987 I would have thought you already have a 38mm idler shaft? Could you not get away with just the gears?

I need to correct that, it's actually an 85 model year. I could replace just the gear, but boy math is paying $1k+ for all new gears vs $150 on a new high speed gear because it's basically like 15% off... was also planning on eventually putting these gears in anyways so will be saving myself some trouble down the road.
 
"Minimal clearancing" 😆

Weld something on there before machining. It's a bitch to fill a hole back in.
My understanding is that's just for the 4:1 gear set? 3:1 just a bit of grinding right @fjdiesel?
 
My understanding is that's just for the 4:1 gear set? 3:1 just a bit of grinding right @fjdiesel?

I've got the 3:1 set and the machinist burst through the case and DJ got to weld up an oily piece of aluminum foil
 
I clearanced mine myself and did not go through the case. But I have heard you have to be careful. I kept putting the case half on and turning the gear until I didn't see and rub marks.
 
I clearanced mine myself and did not go through the case. But I have heard you have to be careful. I kept putting the case half on and turning the gear until I didn't see and rub marks.
This look like what you did or more like a 4:1 machining? Did not say which gear set this was machined for.

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Guess I'll pick up some aluminum rod and start practicing with the TIG

Way easier to build it up before there is a hole there. Talk to DJ, I'm sure he has a solid plan.

I'd be curious how the machine shop did it. I was thinking you'd clamp it down in a mill, find center, and hit it with a fly cutter.
 
@DirtSniffer Yes, that looks like what I did.
 
Cruiser Outfitters stock was unfortunately inaccurate, would be at least mid july if back ordering. Looking at other options. Also looking at the 2.99:1 gear set with 10% overdrive, would drop highway cruising rpm enough that regearing diffs would not be needed. Unfortunately they don't have that on hand either. Waiting to hear if valley hybrids happens to have it.
 
Rear caliper brackets came, have some clearance issues to work out. Can not mount on the back, actuator hits the fat radius arm end. Can not mount on top, will hit the frame under flex. Can fit it on the rear if mounted low, but I think they will get smashed by rocks. Right now the best option is looking to be swapping sides and mounting to the front of the axle. I have one position that works after cutting off one of the wire clips. I think this will require extending the bump stops as the actuator sticks up about as high as the bump stop. There is one more position that rotates it further down, but it hits the radius arm nut. I think that with some minor, careful grinding on the plastic actuator housing, it could fit. This would be the ideal spot as I think the bump stop would protect it from hitting the frame.

On the topic of bump stops, I got a set of trail gear 140053-1-KIT bump stops that would have been a perfect swap for the originals, but I snapped 3 of the 4 bolts for them. So, I may weld something on anyways to fix that and extend it down some.

Cutting off the wire bracket.
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Position that works, but may need bump stop extension.
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Baaaaarely fits.
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Low mount option on rear.
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Low mount on front. Probably the worst option.
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Ideal position with some actuator clearancing.
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Hitting the radius arm bolt.
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Could you put the radius arm bolt in the other way? Maybe more clearance with just the head on that side...
 
Could you put the radius arm bolt in the other way? Maybe more clearance with just the head on that side...
I'm considering trying, but don't think it'll make much of a difference as it'll still hit the bolt head. It won't take much grinding to clear it. No idea what these look like on the inside tho, I'm sure it'll be fine.
 
On a vehicle with a 13" wheelbase, I don't feel disc brakes bring much to the table.

What was the drum setup before? It didn't have the parking brake in the drum?

Or are you trying to setup cutting brakes as well?
 
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