Manual/Standard Transmission guys

[reporter000001]

Im interested in doing a auto to standard swap, Im aware of the high hump, cross-member, drive-shaft, neutral switch and possibly rear diff u joint issues.

Im curious of: what trans you have, 3 speed or 4 and crusing highway speeds, also if anyone has done a 90's 5 speed swap.... isues?

I have access to the hard parts but im curious if its worth it or just getting a 700r4....I sure do hate automatics but im open to a debate.

For instance, with a 90s manual, are you using the stock clutch/brake foot pedals or aftermarket?

Its time for a tranny and ive got to decide what I want to do, sure the stock th350 would be easy but blaaahhhhh.... no over drive and honestly I drive rough and would rather have the human interaction...

thoughts? whos done a 90s swap? if manual 3/4, what are your speeds like? Ive seen the top loader 4 speed heavy dutys, they look waaayyyy over built but look like a tower no freeway......

its a pre78 short single gas tank 350 low hump 1/2t 2wd

[Mikec10]

I have a old 350, with a nv3500 bolted to it. It used to have a 5lm60 which sucked. I like my nv3500, I use a regular 12" chevy clutch. I am upgrading to a EFI 5.3 and keeping my nv3500. First gear is pretty low in the nv3500, something like 1.52 or something.

[csdineley]

I swapped my th400 for a sm465 (4 speed). I would love a nv4500 (5 speed) but they seem hard to find and expensive, at least in my area.

As for highway speeds. I currently have 4.10 gears and 70 mph is doable at 3000 rpms. Eventually I'm going to swap axles and the new one has 3.42 gears in it. So 70 mph will be about 2500 rpms. But I also don't drive at those speeds very often, Mostly just 55 mph.

[slammed48]

I put a T5 in my 73...

I use stock pedals with new linkage with heim joints.

I have not been able to find any aftermarket pedal set ups.

as far as gearing, make sure to take the whole package into consideration...

-what RPM is ideal for your engine
-rear tire diameter
-actual transmission ratio for overdrive
-obviously rear end ratio


I have a 2.73 rear with 29" tall tire and .86 5th gear... which puts me at 2050 RPM at 75mph... I hauled a motor in the bed 1000 miles and averaged 18mpg.

[cerial]

A sm465 will bolt right in without any issue using parts from another truck and bolting everything right up for the most part. I am actually weird and like the direct feel of a mechanical linkage. But, if you want hydraulic post 84 trucks have it.

The sm465 is a 4 speed toploader and most of the time you will only use 3 speeds. The gap between 2nd and 3rd is quite sever and 4th is a direct ratio. There are a few issues with the shifter popping out of gear but it is a easy fix and well documented.

That being said it is a very tough transmission and take tons of abuse. This is a dump truck transmission don't expect to be slap shifting this thing. People have put great amounts of torque (500+ft/lbs) through these without concern, ran them with little fluid, and other crazy things and the trans just laughs and keeps going.
In our trucks I have found that 4.56 or 4.11 gearing works best with the sm465. This allows you to take off in 2nd and get up to around 15-20mph. Then you can shift into third and as long as you keep it above 15 mph you simply only need to switch between 3rd and 4th during city driving.

I try to run as much gear as I can because more gear=more torque if properly set up.
More torque=more acceleration(if properly set up). This all means that you can use a smaller engine that works less under 55 because instead of the engine working the gearing in the rear is doing all the work.

The 4.11's or 4.56 will increase your highway rpm and you will need to really consider what your engine is happy with running. I don't mind running 4,000 down the highway for short periods because 90% of my driving is under 60mph. The percentage of increased torque in a 4.56 over say 3.73's is 18.2%. That means if your engine puts out 300lbs in direct with 3.73's it will put out 355lbs with 4.56 and that is a difference you can feel.
While 2.73's are great for highway cruising they are horrible for acceleration and require the engine to work harder to move the truck around resulting in worse city mileage. A early 70's Cadillac is a example I use a lot here. They had 500lbs of torque and weighed a bit over 5,000lbs(close to our trucks). MPG wise the car got mileage in the high teens at highway speeds. With all that torque could still let you know you had a big block at highway speeds. But, because of the 2.28 gearing the car had a horrible STOCK acceleration of 15+ seconds. Most are around 17 second quarters in stock trim. Put more gear in the same car (and make the engine oil properly at higher rpm) and you have a tire smoking beast that any Chris Ledoux fan can relate with.

If you find yourself cruising down the highway frequently a T-5 is a great transmission for torque under 350ft/lbs. Yes, I know they can handle more with modification. But, I am talking about one you will pull out of a typical junk yard truck or entire donor with no modification done to it and 100k on the dial.

It will bolt right up and you can use the donor/parts truck parts to make the swap tons easier. The difference is that you get overdrive. I would find a donor truck for less then $600 with a new(ish) clutch/flywheel and a blown engine kind of deal if I ever did a t-5 swap because it will let you have all the little things within walking distance.

For a good mix of acceleration and mileage 4.11's with a t5 and a engine putting out around 330ft/lbs is a proven setup that will get you mileage in the mid teens while still being able to light the tires up from time to time. Most factory trucks came with 3.73's which is a 10% drop in torque and not really worth the 400 or so rpm your going to loose at highway speed unless you spend a lot of time on the highway. I would not spend the cash to do a gear swap from 3.73's to 4.11's though. If you have the donor truck with 3.73 and yours is already 4.11 you have "options".

Now, to be fair don't throw out the idea of a automatic just yet. They can handle lots and lots of torque. You can install slap shifters for that human interaction or just sit back and go. As far as automatics go I am a fan of the th400. They are cheap and plentiful and can handle 500+ ftl bs without concern with little or no modification(do your homework). They are the 350 of transmissions and what you can do with them is endless.
I am actually a bit fascinated with the newer "self contained" zf 9 speeds out now. With a .48 (final) overdrive that means you can run some serious rear axle gear. Soon as someone makes a true standalone package this transmission will become a lightweight hot rodders wet dream and knock down quarter mile times significantly.

I tend to drive stupid and as fast as I can so having gearing that keeps me under 60 in a truck that feels scary going 95 is my method of self control while being able to pull away from most people at a stop light. Your experiences will vary.

Our trucks were not really designed to be fuel sippers. I have found the best way to get mileage in the teens with 4.56 gearing is to put the truck in neutral and coast most of the time. I can get easily double the mileage in my truck that weighs 7,880 lbs (Right now. 6060 empty) taking back roads at 60mph then dropping it in neutral coasting to 50 dropping it back in 4th and getting back up to 60 again then going down the highway at 4,000 rpm and getting 7mpg.
I have clocked 16mpg on many 200 mile round trips using this method. The back roads follow the highways in Mid Michigan with few stops if you use the proper routes and it works because of that. I could never do this in say Pennsylvania and imagine you are going to have a situation with not being able to do this due to the layout of your roads.

[andrewmp6]

If you got money a t56 or tko trans.

[86c20]

i have asked alot of trans swap ? as i have the sm465. and looking for the better splits and an od. now i will say that i am not nice to trans at all. my c20 i am wondering why i have not blow that trans up yet. i will race anyone at any time i am also the one to go pull some one ouit of a ditch or drag something across the yard that is way to heavy. this is what i have found and will work for what i have planed later on for the truck as i dont want to do things twice. i will need a nv4500 6 speed or a road ranger 10. now before any one says you dont need a 10 speed stick i am going with a 453t detroit diesel so power is in a vary small window. now it really comes down to use. i use mine alot for highway and towing in town. so i need low and hi gears. ask your self this before you make up your mind or you will wish you had gone the other way. now if it is just you want a stick over auto and just want to play alittle and still have a work truck. sm 465 have one over 300k on it its loud and lot of play but i can not kill it.... no way would other trans come close to takeing what that one has. that is also in a 10k wrecker with pto on the trans. if you are making power, racing or what ever you will want something that shifts better. sm i love but it is a real truck trans.

[Bigstevex4]

I have 83 c10 with 250 six and the 465 i little over kill the gap between 2 and third is huge they have one with a lower third then the jump to 4th is long.
IF it was me i would get one of those Richman 4 speeds jegs have lots ratios to choose from or saganaw or muncie. The hump i wouldnt think would be a problem. you would have 4 gears. the 465 1st is good if your feeding cows. i would put my blazer in 4 low and granny get out go take al leak go get back in.

[greg64]

reporter, wow there's a lot of interest in this topic. I have a 77 1/2 ton with a straight six, and 3.42 rear gears. Used to have a TH350 until it died. I really wanted to go manual, but at the time, there was no affordable overdrive stick. So I used an SM465. I like the 465 for what it is. The gear spacing is too wide (as others have mentioned), but when pulling a trailer, I like the granny low to get the load started. At 60 mph, I'm at about 2600 rpm. That's as fast as the old six wants to go.

Now, in my 64 suburban, I'm using a NV3500 from an early 90s truck. 5 speeds with overdrive and a lot better gear spacing. Also setup for a hydraulic clutch (both my rigs have hydraulic clutches). Wow, is that tranny ever smooth in shifting. I really like it. The only problem with it is that this transmission cannot be disassembled or rebuilt at home, the way a 465 can. It takes a lot of special tools (which I hate). It also takes special fluid (and different from the NV4500). I have a 283 with a torque cam, and with 31" tires and 3.73 rear gears, 60 mph is about 1700 rpm. Cruises along nicely, but I need to downshift to 4th for any significant hill.

The interesting thing is that the suburban is 1000 pounds heavier and is taller, but gets better mileage. A great engine/tranny combo. If I was going to do the rear end again (I've already replaced everything once), I'd use 4.11 gears to make 5th a bit better.

I love/hate the NV4500. No doubt it's tough, but there's the 5th gear nut problem (ya, it can be fixed), the super expensive and special fluid, and the gear spacing isn't any better then a 465, it just has OD.

The NV3500 is the best "cheap" option in my mind. If you can spend a lot more, I'd look at the TKO500, or a SM465 with a gear vendors on the back end. I dream of having an 8 speed SM465...

To me, the T5 is just too wimpy for full sized truck use. I had a T5 in an S10 years ago. It worked okay, but when you looked at it, it was clear it was a wimp.

[BigMike608]

mine is a 4 speed Muncie currently being converted to automatic

[Bigstevex4]

Originally Posted by BigMike608

mine is a 4 speed Muncie currently being converted to automatic

what kinda shape the muncie in? are you selling it?

[BigMike608]

Originally Posted by Bigstevex4

what kinda shape the muncie in? are you selling it?

no it's not for sale, it's already spoken for...