Cracked Transfer Case Today (1 Viewer)

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H42 from a 60 series with the split case could be an option too ,
it give you a better shift cane location, a stronger t-case and no driveshaft modification
You can get the parking brake for the split case from vendor here
I think your crossmember can be use with the split case but you can modify or build a 60 type support
 
So I'd appreciate the details on how much work this is really Does this bolt up to the stock FJ40 T-Case? If not, then I'm looking at ridding myself of the T-Case Cross member (for the Chev V8 conversion) and possibly changing drive shaft lengths regardless. By all means, tell me the steps and hiccoughs in going to the H55 at this time.

It's not trivial, but, much depends on what you have already. Do you have the H42 4 speed or a J31 3 speed?

There are 3 different transfer cases offered in FJ40. A 1-piece '3 speed' t-case found behind the 3 speed transmission, a 1-piece '4 speed' t-case found behind the 4 speed transmission, and a 'Split Transfer case' found in later (8/81) FJ40 and FJ60 Land Cruisers (not to mention other models found outside of the US, but we won't go into those details).

You have a (broken) 1 piece t-case. So you need to replace it. Since you have a V8, it would make sense to upgrade. An Orion would be a bolt in affair, provided the needed donor pieces from your 1 piece transfer case are in good shape. If all of those pieces are scrap you're going to need to find another donor t-case.

A split case was found in nearly all Land Cruisers after 8/81. It is stronger, and has a wide variety of low range gear ratios choices (1.9:1, 2.3:1, 3:1, 3.3:1, 4:1). And you can get them new from Toyota or a variety of vendors (Cruiser Outfitters is my favorite).

If you have a 4 speed Land Cruiser transmission, the bellhousing has the appropriate pattern for an H55, though you may need to do some clearancing for the bearing retainer. If you have a 3-speed transmission, or a SM420/SM465 you'd need to get a new bellhousing adapter from Advance Adapters (and then you may also consider an NV4500 or TR4050... This can become a slippery slope).

You will not retain the 'propeller' cross member, but as other have stated, that is a source of leaks for V8 conversions anyhow. A new cross member that supports the transmission and t-case from the bottom using a rubber isolator will be needed. These can be sourced from an 8/81 and newer FJ40, FJ60 (with modifications) or fabricated from scratch.

You can get a t-case mounted parking brake, but those pieces add quite a bit of cost to the conversion. You can also get a 8/81 or later rear axle and swap that in for the axle mounted parking brake. That said, I see that you have rear disc brakes and based on the photograph, I assume it's the common Monte Carlo rear disc brake conversion. You can get Cadillac El Dorado calipers which should bolt in place and provide a parking brake from RuffStuff (no affiliation, blah blah blah).


Finally, yes, driveshafts will need to be modified.

I've probably missed a few things here, and I am sure others will chime in on those details.
 
I fabricated my transmission support crossmember. This is under the AA adapter for an NV4500.

Crossmember.jpg
 
There is a early three speed with a different case.
It's not trivial, but, much depends on what you have already. Do you have the H42 4 speed or a J31 3 speed?

There are 3 different transfer cases offered in FJ40. A 1-piece '3 speed' t-case found behind the 3 speed transmission, a 1-piece '4 speed' t-case found behind the 4 speed transmission, and a 'Split Transfer case' found in later (8/81) FJ40 and FJ60 Land Cruisers (not to mention other models found outside of the US, but we won't go into those details).

You have a (broken) 1 piece t-case. So you need to replace it. Since you have a V8, it would make sense to upgrade. An Orion would be a bolt in affair, provided the needed donor pieces from your 1 piece transfer case are in good shape. If all of those pieces are scrap you're going to need to find another donor t-case.

A split case was found in nearly all Land Cruisers after 8/81. It is stronger, and has a wide variety of low range gear ratios choices (1.9:1, 2.3:1, 3:1, 3.3:1, 4:1). And you can get them new from Toyota or a variety of vendors (Cruiser Outfitters is my favorite).

If you have a 4 speed Land Cruiser transmission, the bellhousing has the appropriate pattern for an H55, though you may need to do some clearancing for the bearing retainer. If you have a 3-speed transmission, or a SM420/SM465 you'd need to get a new bellhousing adapter from Advance Adapters (and then you may also consider an NV4500 or TR4050... This can become a slippery slope).

You will not retain the 'propeller' cross member, but as other have stated, that is a source of leaks for V8 conversions anyhow. A new cross member that supports the transmission and t-case from the bottom using a rubber isolator will be needed. These can be sourced from an 8/81 and newer FJ40, FJ60 (with modifications) or fabricated from scratch.

You can get a t-case mounted parking brake, but those pieces add quite a bit of cost to the conversion. You can also get a 8/81 or later rear axle and swap that in for the axle mounted parking brake. That said, I see that you have rear disc brakes and based on the photograph, I assume it's the common Monte Carlo rear disc brake conversion. You can get Cadillac El Dorado calipers which should bolt in place and provide a parking brake from RuffStuff (no affiliation, blah blah blah).


Finally, yes, driveshafts will need to be modified.

I've probably missed a few things here, and I am sure others will chime in on those details.


Toyota used seven different versions of transfer case in the US. The early to mid 63. Mid 63 on three speed s. 1/74-4/75 four speed case. Four speed 4/75-4/77, 4-77-7/80, 8/80-9/82 and 10/82-9/83. The 4/77 shows as a sub for 4/75-4/77. I know 10/82 part of the change was the fifth gear oiler in the split case. Would use that one even if going with a four speed in case decide to go H55F later.
The three speed transfer case had narrower gears. The 1/74-4/75 the low range of the idler gear and low range on output shaft were wider. 4/75-7/80 all the gears were wider. Someone with more knowledge probably knows for sure but thinking can use early parts in a later case but will need to add shims for the narrower gears. Using wider gears in an earlier case would require trimming the case. Only switching around I have ever done is the 1/74-4/75 four speed input gear into my 68's three speed case. Idler gear was original with the thinner gears. This way kept the 2.13 low range. The early four speed with low range only having wider gears was 1.99 not 2.13. Some elses not disgusted is differences in the case itself. Earlier were suppsed to be more brittle. Later were softer but had more ribs added for strength. The few times I needed to work on a transfer case just threw in a used case. Quietest one piece case I have ever had was one of my $25 cases I purchased I put in my FJ45. While weaker than the split transfer case the one piece case are easier to change out. When I changed the one in my 45 it took me a couple hours. Stock six with bellhousing motor mounts and torque tube is further back on the pre 1/79 45s. Those two things made it a simpler change. While stronger the split transfer case requires disassembly to remove it from the transmission.

Pretty sure the lower gears over 3.0:1 for the split transfer case are aftermarket. The 4.0:1 require trimming the case to fit.
 
I just drove a short distance tonight. Came around a corner and sort of missed second gear. (didn't fully clutch and I came off the gas. Truck lurched a bit as the engine deceleration slowed the truck). Seconds later in second gear under mild acceleration, big floor board boom then gzynk, gzynk, gzynk all the way home. Transfer case cracked vertically close to the passenger side rear.

So this is an open query on some recommendations on how to proceed /repair/replace. What likely happened internally? What are my first moves?

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This was one of the reasons I decided against putting a V8 in my Land Cruiser with this cross member. The housing was not designed for the stress.
 
This was one of the reasons I decided against putting a V8 in my Land Cruiser with this cross member. The housing was not designed for the stress.
I don't believe the crossmember is the reason for the case cracking. It's the offset rear output t/case and putting all the power thru an idler shaft and gear which is installed in an aluminum case. Actually it's not because the case is aluminum, it's more the design of the case. I've broken both Toyota and Dana model 18 cases which are cast iron. Its just a poor design. Thru the yrs Toyota and Dana both were continually upgrading their designs till finally they offered something different. They're are things you can do to limit the odds of breaking the case.
 
Years ago when I was working in the Portland, OR area, we found a shop in St Johns that was the first time I had seen a broken Birfield outer section and the owner of the Land Cruiser had a Chevy 400 under the hood and he claimed it was making 400 HP. He broke the Birfield on the counter and told he had broken 4 transfer case housings and was having a cast iron housing made to prevent future breaks. He also said every time they broke he had it on the pavement in 2wd and had a very heavy foot.

The Toyota design is for the transmission and TC to float as the engine torque comes on but this crossmember will not allow the transfer case to float and is held stationary under torque.

Later AA came out with a V8 kit for the NV4500 which included a crossmember to install under the transmission. I have an H55F and a split TC for my build and I am still not going to use a V8 for my repower.
 
The OP already has a V8, so he has to deal with what he has. He either has to replace the 1 piece tcase and I'd ad a tcase saver and drive a little conservative or come up with a different setup. Dumping the clutch, burnouts on blktop, or jerking the driveline can break the case or the rear-end.

Back in the late 80s early 90s, I installed a lock rite in the frt, and started breaking birfields. I probably broke 3 or 4 tcases running sbc's and a BBC. My rig was wheeled and raced hard. I started collecting 4speeds/tcases and birfields. Then went to dana 18 t/cases which were maginally stronger and had a lower 2.46:1 low range. Then went center rear output w/a Dana 20 tcase with dana 18 gears. I no longer have any problems. Off set rear outputs by design are trying to spit the idler out the bottom of the case. My street rig is a sbc, nv4500 and stk 40 case. I have to be conscious of what I'm doing and when. It's gas pedal goes to the floor.
 
A TON TO THINK ABOUT
Thanks people. So its a 77 4 speed transmission. Dog is gone on 2nd and have been gently grinding that gear for years. I'm well along in puling the t-case. Built a telescoping cross member tonight to support the drivetrain when I remove the propeller and t case this weekend. I'll look at the guts of it soon.
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The OP already has a V8, so he has to deal with what he has. He either has to replace the 1 piece tcase and I'd ad a tcase saver and drive a little conservative or come up with a different setup. Dumping the clutch, burnouts on blktop, or jerking the driveline can break the case or the rear-end.

Back in the late 80s early 90s, I installed a lock rite in the frt, and started breaking birfields. I probably broke 3 or 4 tcases running sbc's and a BBC. My rig was wheeled and raced hard. I started collecting 4speeds/tcases and birfields. Then went to dana 18 t/cases which were maginally stronger and had a lower 2.46:1 low range. Then went center rear output w/a Dana 20 tcase with dana 18 gears. I no longer have any problems. Off set rear outputs by design are trying to spit the idler out the bottom of the case. My street rig is a sbc, nv4500 and stk 40 case. I have to be conscious of what I'm doing and when. It's gas pedal goes to the floor.
A picture or two of your current undercarriage set up would be nice to see
 
The 40 with the nv4500 has the stk 75's tcase and has the propeller. It probably looks just like yours except 8" further back in the frame. The po had it installed. Nv4500's are long. I plan on getting a tcase saver and call it done for now. I still have my collection of tcases.
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The center rear output 40 runs a gm 4 speed, dana 20 case and a centered 40 rear. I'm not sure you want to go there. It all depends how you're going to use the 40.
 
The 40 with the nv4500 has the stk 75's tcase and has the propeller. It probably looks just like yours except 8" further back in the frame. The po had it installed. Nv4500's are long. I plan on getting a tcase saver and call it done for now. I still have my collection of tcases.
View attachment 3103868

The center rear output 40 runs a gm 4 speed, dana 20 case and a centered 40 rear. I'm not sure you want to go there. It all depends how you're going to use the 40.
No. I think I’ll just build it back like it was for now But the discussion on this thread gives me an idea. It was my opinion all along that the propeller cross member resisted the drive trains torque too muck ( even with the rubber frame rail mounts. ) I might refabricate the bolt up point so the t case can spin a bit on a ring bearing. That would eliminate all torsional forces
 
Sounds like the transmission needs to be rebuilt and is easier to remove them together. For one, when you pull the transfer case it is heavy on the output side and will rotate to 6:00, two they share the output shaft of the transmission. There is a thrust washer on the back end of the transmission that has an anti rotation notch that lines up with a pin in the output shaft and if that washer gets displace on assembly the entire gear train will lock up because it takes out all the thrust clearance. It will also throw off the shift rails.

Get some 12M, I think, is 1.5 thread pitch all thread that will thread into the holes where longer bolts go through the adapter between the transmission and transfer case it will help stabilize the TC. I assembled the two boxes on the bench using the all thread. There are two bolts inside the PTO cover that will have to be removed.

I pulled the transmission cover and used a rope to lower the transmission and transfer case in mine back in the 90s.
 
When I was running the stk case I did not tighten the propeller frame bolts too tight, and the driver side was a little loser. I also had the engine mounts tight.
I've worked on a lot of CJ's & YJ's and found j**p used a torque arm extending towards the driverside with their transfer case center mounted to allow the driveline to twist or lift slightly. Their frt motor mounts were the normal rubber type and allowed the driveline to twist or lift. The SBC in a 40 basically has solid mounts with a bolt going thru a puck. I was trying anything to limit breakage. Folks have cracked and broken cases with the stk 6 and with the tranny/tcase hanging off the back of the bellhousing and no crossmember.
 
Built a three point jig/bracket that worked like a charm. But I had to sawzall 3/4 “ of the passenger side propeller bracket to make clearance to remove the t-case Sorry. Some of the shots are foggy ( too much case oil on my hands)
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That worked well you were able to control it from swinging.

Looks like the output shaft has wear on the splines where the input gear rides. Check the splines on the gear and see is they are worn also. Both may need to be replaced and are available. Had to do it when I did the rebuild of the gearboxes.

After doing a rebuild of an H42 and the transfer case and seeing how to work on a split case disassemble and assemble are much easier.
 
Not sure what kind of force I need to get this out. I have an arbor press but …. No Go

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Wack that shaft forward with a bfh to knock out the freeze plug. Then wack it towards the rear with a large drift. It will come out.
I have a used 34mm one piece case and gears if you need one.
 
They are a slip fit the case must be twisted. A spilt case would be a better way to go, you will need the adapter plate that will allow it to bolt up to the 4 speed.
 
They are a slip fit the case must be twisted. A spilt case would be a better way to go, you will need the adapter plate that will allow it to bolt up to the 4 speed.


Would still need to deal with the sixteen spline verses the nineteen spline tailshaft the split case input gear has to ride on. A cheap 60 series transmission and transfer was listed in the classified lately. The four speed top cover could be switched but with the V8 the 60 series is a better fit.

Has it been determined if this is one of the 8/80+ one piece transfer cases with the large idler gear shaft like @65swb45 mentioned earlier in this thread? In the US those are a white elephant as far as finding parts. Would be 100% sure of the condition of all the internal parts before even thinking about repairing the case.
 
The shaft the idler rides on may have a shoulder on it due to bearing wear, try lifting or shifting it by hand as you tap with hammer, the above suggestion to first tap out freeze plug then push/tap shaft toward rear of case, it will come out that way.
 

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