Bang Bang
Age is a state of mind.
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- #141
Mike's 78FJ40 Build Thread
- Thread starter Bang Bang
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That would just be Deryl trying to stir the pot AGAIN! What he fails to remember is that Hachi may buzzz or be the bee or whatever but she did lead a few rides at GSMTR, was loaded on to the trailer under her own power, didn't try to make a roman candle out of herself, made the trip to Sicily Island there and back through a tropical storm and will be going to Superlift. Let's ask him about his not-so-mean green JD tractor.
Mike the tractor comment hurts
All statements are close to true except for the loaded on the trailer under its own power. Brutus has never lacked on the power category. As for driving Brutus thru a tropical depression...........well thats not my cup of tea. Once Brutus awakes again (hopefully sometime this year) he will be looking for some honey to have with his breakfast!
Bang Bang
Age is a state of mind.
- Thread starter
- #143
Just trying to keep Lance in the loop
.........oh, and don't get your feelings hurt. I only said tractor once. 
Just trying to keep Lance in the loop
Oh I understand now>
Bang Bang
Age is a state of mind.
- Thread starter
- #145
Not much done to her since my last post. I added the KC lights to the windshield. But I did purchase some "new-to-me" drivetrain parts from the bellhousing to the t-case.
This is going to be installed in the next couple weeks: SM420 / AA Rock Box / Toyota 3 speed t-case.
SM420: Has less than 500 miles on it (PO bought it brand new, military version). It's a 4 speed with a granny 1st. Will give me the lower gearing I was looking for.
AA Rock Box: Gear reduction box with less than 500 miles also. This was a bonus as I wasn't really looking for this.
Toyota 3 speed t-case: takes care of my leak issue in mine. Although, I can see where the PO was having the same issue I was with rubbing, just not as severe or in the same location.
This is going to be installed in the next couple weeks: SM420 / AA Rock Box / Toyota 3 speed t-case.
SM420: Has less than 500 miles on it (PO bought it brand new, military version). It's a 4 speed with a granny 1st. Will give me the lower gearing I was looking for.
AA Rock Box: Gear reduction box with less than 500 miles also. This was a bonus as I wasn't really looking for this.
Toyota 3 speed t-case: takes care of my leak issue in mine. Although, I can see where the PO was having the same issue I was with rubbing, just not as severe or in the same location.
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It even came with a T-case crossmember, nice set up.
Bang Bang
Age is a state of mind.
- Thread starter
- #147
Oh yes it did. You can't see it but it also came with a home made tranny cross member that I probably won't use unless it looks like it needs it. I asked the PO about it and he said he just likes overkill and didn't think it was necessary. Got the whole set-up sealed and ready to go for less than the cost of a new rock box alone (if they were still available).
Bang Bang
Age is a state of mind.
- Thread starter
- #148
So, I finally got around to getting the new-to-me driveline installed this weekend. It is not complete but the really hard $hit is out of the way. With lots of help from lots of friends, we got it installed. I still need to fix the clutch slave, get the drive shafts re-worked (or get new ones), fill the cases with gear oil and install the revere switch. She is getting there......
Jeeze, you just did that.
You've had that planned since I went get the springs..
Should work better and quieter than your previoius set up.
Thanks
Cody
You've had that planned since I went get the springs..
Should work better and quieter than your previoius set up.
Thanks
Cody
Bang Bang
Age is a state of mind.
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- #150
Better....yes. Quieter.....not so sure.
Thats a good bit of work you guys knocked out quick.
Looking good Mike gonna be a nice addition for sure 
Bang Bang
Age is a state of mind.
- Thread starter
- #154
Thanks guys. It sure was a learning experience. I hope to have her on the road by next weekend.....if the drive shaft place can get me taken care of this week.
Nice , How muck slower to you think it will go now? Crawl ratio?
Bang Bang
Age is a state of mind.
- Thread starter
- #156
Not sure how to calculate it but if I remember it is something like 160:1 in Lo 1st 4-Lo. It should be nice and slow.
Bang Bang
Age is a state of mind.
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- #157
So the SM420 and the 3 speed t-case will be at 67.5:1 and the rock box is 3.44:1. So how do you figure out what the final low gear ratio is?
(67.5*3.44*diff ratio)rpms : 1 turn of the tire
Bang Bang
Age is a state of mind.
- Thread starter
- #159
Well, if those figures were right that would put me at 954:1 which isn't right. So, I went and did more research and I think I found it:
SM420 - 7.01:1
Rock Box - 3.44:1
3spd t-case: 2.31 or 1.99 (I am not sure what year case it is but it won't make that much of a difference)
diffs - 4.11
So, it's either 228:1 or 196:1 depending on which t-case I have in this set up. Considering that my ratio was 33:1 before the swap, this new set-up will be a world of difference.
SM420 - 7.01:1
Rock Box - 3.44:1
3spd t-case: 2.31 or 1.99 (I am not sure what year case it is but it won't make that much of a difference)
diffs - 4.11
So, it's either 228:1 or 196:1 depending on which t-case I have in this set up. Considering that my ratio was 33:1 before the swap, this new set-up will be a world of difference.
I thought the 67.5:1 seemed about 10x too high, but I have no idea what you're putting in that thing....and behind a SBC too!