Decision Time sm465 or nv4500

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saryon7

saryon7

10 Year
Joined
May 14, 2011
Threads
32
Messages
313
Location
NorCal
73 fj40
I am doing an engine swap soon to a sbc 350 and I need to decide on which transmission. I do mostly around town driving, but one goal is to be able to easily drive to Tahoe which is about 3 hours away and about 8000' elevation. I want to be able to be capable off road, but will probably never do any hard core rock crawling. More trails for camping kind of deal.
I would really like to hear from people who know these transmissions. I don't like the really high price of the nv4500 and the extra expensive AA adapter that goes with it, but I wonder if I go with the sm465 that I might regret not having the overdrive. So school me on what people think of these transmissions. What is the better choice? And I will be using the stock 3 speed transfer case.

These are the prices I see in my area:

sm465 $100
rebuild kit if needed $250
AA adapter $500

nv4500 $1000
rebuild kit: not sure
AA adapter $1200

So, that seems like a huge price increase for overdrive. What do you guys think? Smarter to go with the sm465?

One last thing... Sbc and sm465- will the shifter end up pretty close to the stock location?

thanks for taking the time to help :cheers:,

john
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I've been running the SM420 which is pretty similar to the SM465 for running around.
Off the road, the SM420 is probably the second best modifications I've ever done to my truck for offroad use (the first being power steering).

I do sometimes wish I had an overdrive for long jaunts on the highway. Around town and on the trails, no big deal though. I am running 4.88's though and when I had the stock 4.11's in the diffs, lack of an overdrive wasn't much of a big deal.

Have you considered an automatic like a 700r4 or 4L60?
I think that if I were going with a GM V8, I'd do an auto instead of a manual, but that is my silly opinion.
 
I had a 350 sm465 combo in a j**p with 39"s and there is no way I would have wanted to drive it 3+hrs for a few different reasons.
1) non sychronized tranny=not such a smooth highwayshift
2) 1st gear is so low that its more like a 3sp with a granny gear 1st=6.5-1
That being said I loved having such a low first gear for off roading
Good luck
 
I am facing the same decision in the next two weeks. I am replacing a tired 327 + sm465 with a new 350 and a different transmission. My driving routines sound very much like yours. Would like to drive 4 hours to mountians vs trailering and with the low geared 465 stresses truck on interstate/state hwy. Cost/benefit is also an issue. Considering both nv4500 and toyota 5 spd. I am trying to determine if nv4500 w/a adaptor will fit current spave vacated by the sm465 w/a adaptor without significant mods. Price seems about same. Good luck with your decision
 
Yes the 465 shifter will fit CLOSE to stock location depending on where in relation to the firewall you mount the engine. Cruiser will do eighty with this combo that said I do wish it had overdrive mostly for less exhaust noise with lower rpm and would need better gas mileage. I'm not changing the 465 unless it's a commuter on the hiway everyday
 
Great recommendation on the 3.70 diffs. Already changed them and it resulted in a noticeable improvement in noise/vibration. Thanks.
 
The NV4500 is pretty sweet. I like mine. It has low gearing for when you need it on the trail and the 0.73 5th gear for the highway. I don't remember the actual numbers, but the 5th gear is the difference between running at say 2200 RPM at 70 mph on the highway or running at 2800 RPM in 4th. I have a 4:1 Orion, so I don't use 1st gear on the trail very often, but do find it useful for crawling boulders rather than playing leap-frog through the rocks. :D
 
I have a 420... I LOVE the first gear... but it's a clunky transmission for driving on the road. I have 35s and 4.11 diffs and I still have to cruise at 60ish on the highway or the motor is just running too hard. I would love an overdrive.

If I had it to do again, I would put a 5 speed in.
 
First of...Thanks for all the replies. I really appreciate getting some input from some experienced people:) Keep em coming, this is some really good info guys.

That is some great advice. I never even thought of that. That way if I do go with the sm465, it gives me a way to still modify for some better street conditions.

Fast Eddy said:
If you're not crawling you could swap in 3.70 diffs and gain 10%. You probably won't notice it much if you're not crawling and it will run nice on the freeway. You can usually find nice 3.70 diffs for $100 or a bit more.
Click to expand...

What do you mean by it being a clunky transmission? Doesn't shift smoothly? Do you know what your rpm is at 60mph?

hairy_apple said:
I have a 420... I LOVE the first gear... but it's a clunky transmission for driving on the road. I have 35s and 4.11 diffs and I still have to cruise at 60ish on the highway or the motor is just running too hard. I would love an overdrive.


Would you still choose the 5 speed if it was a $2000 dollar difference? Just wondering because according to the prices I see, that is about the difference.

If I had it to do again, I would put a 5 speed in.
Click to expand...

What is the rpm around 65mph?

cruiserjunkie said:
Yes the 465 shifter will fit CLOSE to stock location depending on where in relation to the firewall you mount the engine. Cruiser will do eighty with this combo that said I do wish it had overdrive mostly for less exhaust noise with lower rpm and would need better gas mileage. I'm not changing the 465 unless it's a commuter on the hiway everyday
Click to expand...


Thanks guys,
keep it coming I am absorbing it all,
john
 
No tach for me either but doesnt seem like its screaming at 65. I also have 4.11 and 35s. Chevy trucks in the early 80s used 465 so dont think youll have any issues there running the same combo. That said buy once cry once you cannt go wrong with low first gear and overdrive all it takes is money
 
hairy_apple said:
I have a 420... I LOVE the first gear... but it's a clunky transmission for driving on the road. I have 35s and 4.11 diffs and I still have to cruise at 60ish on the highway or the motor is just running too hard. I would love an overdrive.

If I had it to do again, I would put a 5 speed in.
Click to expand...
Same combo I have, except 35's w/3.70's. At 60 mph I only turn 22-2300, purrs at 25-2800, but then your motorvating down the road pretty good. Have got 15+ mpg running around 23-2400 to work and back, 2 lane with hills, light traffic. Basically a 3 spd on the floor w/ granny low when you need it, gotta love hitting 3rd, winding it out some, then into 4th.
 
If you run 33s and 3.70 gears, you'll have about a 25% overdrive. I'm quite happy with a stock 4 speed with that combo, and have even got 17mpg with a 350 and a tired qjet. If you're not crawling, I'd also consider a stock 4 speed... Or even a Toyota 5 speed.

Some have said 420/465s are clunky shifting on the road and that 4500s are smoother shifting.

Randy's Ring and Pinion has a good online calculator for looking at RPMs for different combos.
 
50mph is only 2000 RPM... :D
 
SM420 with V8 -great off road and local streets or short hwy runs. Frequent 3 + hours on hwy would become a drag. I would upgrade in your situation as you will be more likely to enjoy the trip.
 
It's an FJ40. Short wheel base. No reason to run an overdrive. How fast do you really want to go?

AN SM 465 is $100, a NV4500 is $1000+.

Yes, overdrive is nice. But think about it. There are like 5 guys that still DD an FJ40. For them, maybe(maybe) an overdrive makes sense. But for most, an SM465 will greatly enhance your offroad capabilities for basically free and will let you go 65 mph on the highway. That's a great mod.

There are many advantages to keeping your drive train short in an FJ40.

An SM420/465 in good order isn't really clunky, it's just different. The low 1st gear makes up for a lot of short comings and the $100 price isn't bad either.
 
First off, I want to say thank you to all the people that chimed in and offered advice. I REALLY appreciate it! You guys had some great input. After reading through everyone's advice, I have decided to go the sm465 route. I can't justify the extra $2000 that nv4500 trans and adapter would cost. It seemed from most people that the 465 would be fine on the freeway most of the time and since I don't drive the freeway really other than getting to camp sites and stomping grounds, the sm465 seems great. I heard enough good reviews from the 465 that it convinced me.

I picked up a great one from valley hybrids at the swap meet and will now start the long hours of cleaning.:popcorn:
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hey all. sorry to hijack the thread, but site wont let me post my own yet. I too have a 350sbc/ sm465. I have a most unusual problem though. the fj wasn't running when i got it and the tranny was full of water. im trying to get the top cover off to see the damage to the clutch fork (it looks to be rusted.) I did not install the tranny originally but the markings and OAL indicate I do indeed have an sm465. however, I have an unusual shift pattern I think. by moving the drive shaft it looks as if I have L all the way over to the LEFT and down followed by 2nd being up and over, 3rd straight down from there, 4th up an over again and reverse straight down. However, the previous owner remembered R being to the LEFT and DOWN. either way this is not a shift pattern for the sm465 and the local tranny guys say you cant change the shift pattern on this tranny. it is because of the unusual pattern I think that I cant use the half neutral/ half reverse trick to remove the top cover. does anyone have a clue on what I should try in order to remove the top cover? After removing the PTO covers it looks as if the gears are fine, but that fork looks pretty bad from what I can see. anyway to clean it without opening it up? any help is most welcome
 
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