Looking to swap out auto tranny with 4 or 5 speed - existing V8 swap (1 Viewer)

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Steve Abbott

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Sep 9, 2017
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Bloomington, Indiana
Newbie here looking to purchase a clean 1965 FJ40 but I don't have a lot of experience with these things. My attraction to this particular 40 is that is extremely rust free BUT has an existing half-assed 350 and auto tranny swap. If I purchase this, I would really like to swap out the slush box for a 4 or five speed tranny. The existing V8 swap potentially needs redone anyway to solve some clearance issues with the steering column along with a few other small issues. It looks like the current brake booster is installed where the old clutch master cylinder might have been. The 40 also has had a GM tilt steering column hacked into the firewall.

Unfortunately, I don't have a lot of time to research some of these things as thoroughly as i would like due to the pending sale, so I'm posting here to hopefully speed up the research. I'm trying to figure out how feasible and costly these changes will be before I buy this 40. So, the questions are as follows:

1) What are the best manual trannys to swap in with price and availability taken into consideration? A 5 speed would be my #1 choice but it looks like this might require a different transfer case - maybe a split case of some sort???
2) What are the best adapters to mate the manual up to the SB V8 and the transfer case?
3) What clutch / pressure plate parts are recommended for the V8 power?
4) Is there a good source for clutch pedal/parts, clutch master cylinder, brake master cylinder, etc. so I can get things back to fairly stock in the pedal box and engine compartment areas?
5) The transfer case crossmember & mount looks to be homemade. Where is a good place to source a good TC crossmember to use with the V8 & suggested manual tranny?
6) What is the best fitting tilt steering column for this particular 40?
7) I would like to determine if the current V8 motor mounts are in the correct location and if the engine is mounted at the correct height. Is there a source for measurements for this type of thing?
8) Is there anything else I need to be aware of?

Axle / disc brake upgrades will probably be needed in the future but I'm not too concerned with that right now.

Thanks in advance for your assistance! I'll be doing more research on this site tonight and tomorrow, but have to have the deal done for this 40 on Monday or it will be offered to the masses on Tuesday.

Steve
 
Here's what I got off the top of my head

1) NV4500 (common in US trucks) and H55 (Toyota) are both good 5 speeds. The NV4500 will mate right up, I don't know about the H55.
4) Yes, all this stuff is readily available from a variety of sources.
6) There isn't a great one, Idit (or something like it) is a popular option.
7) Mounting location is always custom, but you might be able to get some rough idea from the people on here.
 
NV4500 is cheaper than an H55 but the H55 has better gear spacing. You don't need to run the split case with the NV4500, Advance Adapters has multiple options but you have to chop the output shaft of the NV4500 and sandwich their adapter between transfer case and transmission which adds length to the drivetrain.

In my opinion, H55 with split case would be the "best" 5 speed setup, but not necessarily cheapest and certainly not the only option. You can get a bellhousing for the H55 to mate it to your SBC and from there back it can be all Toyota.

If you poke around, you'll find that that one extra gear will cost you a lot of money! A stock 4 speed and t case from another FJ40 can be used with the adapter bellhousing for much cheaper. You could also use a GM 4 speed and AA adapter to a landcruiser t-case.

Here's what the AA adapter looks like between the NV4500 and my original 1976 transfer case.
IMG_6999.JPG
 
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Thanks for the replies so far. I'm soaking up as much info as I can. I a found copy of the Advance Adapters conversion guide which has been very helpful. Based on my small amount of research, I concur that the LC 4 speed tranny would be much cheaper and easier to install. Is there a particular 4 speed tranny that is better than others in terms of strength, spline count, or availability? Anyone know what RPMs I would be running with a 4 speed and stock gearing at around 70 MPH?
 
The common GM or Cruiser 4 speeds are 1:1 in 4th gear. You'd be north of 3,000 RPM with stock diff gears and stockish tires at 70 mph. Plenty of websites have calculators you can play with to determine RPM based on various transmission, axle gear and tire size combinations.

What auto trans is in it now and what is its condition? If it's in good shape, you might consider getting the rest of the truck fixed up first so that you aren't biting off so much at once.

Some more photos of everything you're talking about would be helpful.
 
With the standard gearing most 40's have in the axles, I can tell you from experience that a 5 speed makes a huge difference if you're going to be doing any highway driving. But if it's not in the cards, then it's not in the cards
 
I was thinking that the early gear ratios were 4.10 but I'm not positive about that. I do plan to run 33's. I am looking for a chart that shows axle differences such as ratios and brake info for the various years. 3.70 gears and disc brakes would be nice at some point if I were to run the 4 speed.

I did find a tranny place about an hour from my house that has rebuilt GM NV4500's, so that is a good possibility unless I can find a good cheap stock 4 speed/TC combo. I might be able to live with the 4 speed until I end up swapping out the axles - assuming I can find a set - but I need to get the rest of the drivetrain dealt with first.
 
SBC, Nv4500, 4:1 Orion, 4.11 gearing on 35's and I can crawl offroad and cruise the highway with ease. Best of both worlds. Do your homework, do it once and the way you want it.
 
I agree - do it once and the way you want. I think I have a good idea what I want to do and how much it will cost now. Now all I have to do is buy the LC in question. So, I think I will have about $3-3.5k in reworking the V8 swap, adding an NV4500, fixing various leaks and getting the brakes working properly. Given what I have mentioned above and the cost to fix, what do you think about a selling price of $9500 for a '65 FJ40 with a rust free body and frame?
 
I did find a tranny place about an hour from my house that has rebuilt GM NV4500's, so that is a good possibility unless I can find a good cheap stock 4 speed/TC combo. I might be able to live with the 4 speed until I end up swapping out the axles - assuming I can find a set - but I need to get the rest of the drivetrain dealt with first.
In early October I'll probably be selling a 4-speed and transfer case (from a '78 FJ55) here on MUD. I swapped the combination into my '71 FJ40 in October 1999 and have only put about another 500 miles on it over the years since. The '71 is being upgraded with an H41 and split transfer case. PM me if you're interested.
 
In early October I'll probably be selling a 4-speed and transfer case (from a '78 FJ55) here on MUD. I swapped the combination into my '71 FJ40 in October 1999 and have only put about another 500 miles on it over the years since. The '71 is being upgraded with an H41 and split transfer case. PM me if you're interested.

PM sent
 
I was thinking that the early gear ratios were 4.10 but I'm not positive about that. I do plan to run 33's. I am looking for a chart that shows axle differences such as ratios and brake info for the various years. 3.70 gears and disc brakes would be nice at some point if I were to run the 4 speed.

I did find a tranny place about an hour from my house that has rebuilt GM NV4500's, so that is a good possibility unless I can find a good cheap stock 4 speed/TC combo. I might be able to live with the 4 speed until I end up swapping out the axles - assuming I can find a set - but I need to get the rest of the drivetrain dealt with first.

'65 would have come with 4.10. I'm in the process of swapping in 3.70 gears from a 60. I got the two 3rd members for $100 and only had to Drill the round flange to match my older drive shaft pattern. I've been running the rear for a few years and am very happy with it. I'll swap in the front when I do a complete axle rebuild.

This means I can't run 4x4 right now... unless it's extremely slippery, and I need to to get unstuck. Not ideal, but sometimes that's the way things work out.
 
'65 would have come with 4.10. I'm in the process of swapping in 3.70 gears from a 60. I got the two 3rd members for $100 and only had to Drill the round flange to match my older drive shaft pattern. I've been running the rear for a few years and am very happy with it. I'll swap in the front when I do a complete axle rebuild.

This means I can't run 4x4 right now... unless it's extremely slippery, and I need to to get unstuck. Not ideal, but sometimes that's the way things work out.


Do you know of a list somewhere on this site of axles and 3rd members that can be swapped into the '65?
 
Steve, I have the 4 speed bellhousing adapter you will need. I also have the transfer-case rear crossmember motor mount you will need. Also, I may want first dibs on buying your auto adapter (depending upon what it is). The Downey V8 installation instruction manual will tell you the best place to put the motor, that manual is posted up here on mud, on the Downey Off Road link, if you can't find it, JohnnyC here on mud can hook you up. Let's stay in contact during your venture.
 
Steve, I have the 4 speed bellhousing adapter you will need. I also have the transfer-case rear crossmember motor mount you will need.
I know the bellhousing adapter will work with a late-'70s Land Cruiser 4-speed, but what about the transfer case crossmember mount?
 
I know the bellhousing adapter will work with a late-'70s Land Cruiser 4-speed, but what about the transfer case crossmember mount?
Yep, works with 3 spd. or 4 spd. transfer-case (same bolt pattern).
 
Steve, I have the 4 speed bellhousing adapter you will need. I also have the transfer-case rear crossmember motor mount you will need. Also, I may want first dibs on buying your auto adapter (depending upon what it is). The Downey V8 installation instruction manual will tell you the best place to put the motor, that manual is posted up here on mud, on the Downey Off Road link, if you can't find it, JohnnyC here on mud can hook you up. Let's stay in contact during your venture.


Sounds good if the timing works out. When are you looking to do your project?
 

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