The Stovebolt Site Forums The Shop Area Driveline T-5 swap into '59 Apache

Hello!

I'm considering a T-5 swap into my '59 Apache 3600, but I'm not sure what's involved. I know that on the AD trucks you have to use an 87 or earlier S10 tailshaft and fab a rear mount, but I have no idea what you have to do for a TF truck. Can it be done? The truck now has an SM420, and I'd like to keep the floor mount parking brake if I could, but I'd have to make it work with the cable parking brake setup on the Dana 60 rear I swapped in a few months ago. Has anyone done the swap? Just looking for words of advice here.

Thanks...

Chris

The T5 is a bit light for a 3/4 ton truck.

There is no need to fabricate a crossmember. You will likely have to remove the carrier bearing crossmember that is behind the sm420. You will also need a new driveshaft made. A 1 piece driveshaft should be fine, but you might need to make it 4 inches diameter.

Find the e brake setup from a 1/2 ton. The pistol grip dash lever will be easier to adapt. You will also need the pulley, rod, and swivel bracket.

Swingdaddy - What other transmission options should I consider? I want the OD gearing that the T-5 offers, and I already have one, although I don't want to use it if it's likely to shred after some use. I don't plan on using the truck to haul anything, although I do want to build the engine eventually. It's a factory V8 truck with a 350.

Chris

Bunch of info here on T5's.
Instead of an o/d have you considered a rear end swap.
1973-1987 rearends bolt in. Look for a 3.08 geared one.

http://www.jalopyjournal.com/forum/showthread.php?t=171291

Gotgas -

Already have a Dana 60 with 3:54 gears out of an 87 Dodge 2500. Was hoping to warm up the performance with more gears, and get an even better rpm on the highway.

Chris

I have a NV4500 in my 59 GMC 1/2 ton longbed with 3.70 rear gears. The OD ratio is 0.73:1 or a 27% od. The MY6 is a 4 speed, 1-4 match up pretty close to 2-5 on the NV4500. The NV4500 offers a 5.61:1 granny gear.

Both are excellant transmissions that are up to the task of a 3/4 ton pickup.

What engine are you running?

Swingdaddy -

It's an original V8 truck that has a '70 350 4bbl engine. Other than the Dana 60 and the non-original engine, the rest of the truck is pretty much stock. It looks like someone swapped the top end of the original 283 onto the 350 block, so I have small valve heads and ram's head manifolds...it's not a tire burner (at least not yet).

What wast the NV4500 used in, and what mods are necessary to get it to fit? Sounds like a good swap, but I know zero about it.

Chris

Google is your friend.
Search for nv4500 and read away.

You need an adapter plate between the bellhousing and transmission like this one.

http://www.amazon.com/Advance-Adapters-712550-Bellhousing-Adapter/dp/B000FPZTP6

This adapter will require extra machining to fit a 1948-1967 chevy or gmc truck. The indexing lip on the adapter plate needs to be cut down from 5.125 inches to 4.686 inches, or the bore in the bellhousing needs to be opened up from 4.686 inches to 5.125 inches.

The 1994-1997 Dodge 2wd NV4500 is the easiest to swap. This version can easily be converted to a mechanical speedometer. There is a heavy duty diesel version, and a lighter duty gas version. Idealy you would want the gas version with the 10 spline 1 1/8 pilot shaft. If you get the diesel version, you can swap out the 10 spline 1 1/4 pilot shaft for a 1 1/8 shaft without getting insde the transmission. You will also have to swap out bearing retainers.

There is a crossover throwout bearing that will work on the larger NV4500 bearing retainer. The bearing retainer can be turned down on a lathe, and the stock gm throwout bearing can be used.

The Dodge NV4500 has a pilot tip of 0.750 inches. The stock pilot tip of most gm transmissions is 0.590 inches. This means a non stock pilot bearing/bushing needs to be used with this transmission.

RECAP:
Dodge 2wd NV4500 from 1994-1997
With a little machining all stock clutch components can be reused except the pilot bearing.
The transmission can easily be adapted to a mechanical speedometer. (later versions and the gm versions relied on a velocity sensor.)

Below are sites of interest

http://www.high-impact.net/transmission_and_gear/nv4500.htm
http://www.novak-adapt.com/knowledge/nv4500.htm

The T5 is still an easier and cheaper swap. If you aren't working your truck too hard it might be ok. Gm never put a t5 behind an engine larger than a 307. I prefer to have more transmission than less... Last week I took some concrete debris to the dumps for a neigbor. I tipped the scales carrying a 2200 lb load. I may have been a bit overloaded for a 1/2 ton pickup, but my point is just that... eventually every pickup is asked to do a little more than what it is rated to do.

Depending on your budget, you can go with a new T5 that is said to support 600HP. Unless you tubbed it though you really won't get that much to the pavement so probably no worries anyway. JEGS has them new from $1300 - $2200.

Swingdaddy -

NV4500 sounds like the way to go.

When you say stock clutch setup, do you mean the stock clutch setup for the Chevy, i.e. flywheel/clutch/pressure plate/throwout bearing/fork?

Any mods necessary to the crossmember and clutch linkage?

Also, how do you convert the electronic speedo drive to a manual?

Thanks...

Chris

When I say stock clutch... I mean stock bellhousing from a 59(You could use any v8 chevy truck bellhousing up to at least 1972. 1968 and later truck bellhousings are already indexed to 5.125, so you might avoid some of the machining mentioned above), stock fork, stock pressure plate, stock clutch disc, stock throwout bearing (some machine work required on the transmission bearing retainer), Stock linkage... You may be able to use a flywheel with a 12 inch clutch (I have an 11 inch clutch in my 59 gmc with pontiac V8.)

The bellhousing crossmember does not need to be modified.
However you will probably want to fabricate a new tail shaft crossmember.

If you have a carrier bearing crossmember, that one can be eliminated.

The NV4500 pushes the shifter about 6.5 inches back from where the shifter would be for the sm420. (GMC V8 motors sit about 4 inches forward of where the chevy V8 and six cylinder motors, so my shifter is forward of where yours would be in the cab)

My post above post might be a little confusing.

Because you would simply be placing an adapter plate between the bellhousing and the transmission, Most of the original clutch components can be reused. This makes ordering parts much easier in the future as you don't have to have a speacial book with part numbers. Just look up the clutch by the year and make of your truck.
I have posted some pictures of the sm420 and the Nv4500 side by side on the oldgmctrucks forum.

The basiscs of this swap is that the dodge NV4500 uses a pilot shaft that is one inch longer than the gm pilot shaft. This allows you to use a 1 inch adapter plate between the bellhousing and transmission. The adapter plate simply bolts up to the bellhousing, and the tran smission simply bolts up to the adapter plate.

Advance adapters could hook you up with a crossover pilot bearing and a crossover throwout bearing that will work with your clutch fork. I turned the snout of the bearing retainer down to match the snout of the sm420 bearing retainer. This extra machining allowed me to use the original throwout bearing. (It has been several years, so don't quote me on these numbers, but I believe the snout of the dodge NV4500 bearing retainer is 1.43 inches in diameter, while the snout of the sm420 is 1.383 inches. That means about 60 thousandths need to be cut off the dodge bearing retainer for the gm throwout bearing to slide over it.

If you are willing to spend 2K you can retain your SM420 and add a Gear Vendors OD. It will also require driveshaft mods.
Fred

Swingdaddy -

Thanks again for the added detail. It sounds like a fairly straight forward swap with the adaptor parts. I'd have to measure my shifter placement vs. the bench seat to see it it would clear, my sense it that it would. I recall reading that one of the conversion parts vendors offers a simple steel shifter handle that can be bent if needed.

How did you swap from an electric speedo drive to a mechanical one?

I found two NV4500s close to me, both are from Chevy trucks, one has the lower granny gear (6.13 vs 5.something if I recall correctly). Any advantage of using one over the other, save for the lower gear range of the earlier model?

Lastly, any interference problems with the exhaust? I want to swap my truck over to duals soon.

thanks...

Chris

Swingdaddy -

A few more questions -

What do you mean when you say that the bellhousing is "indexed"? I've pulled transmissions and replaced clutches, but I don't know what the indexing refers to.

Also, what do you mean by the transmission bearing retainer? Every clutch I've done has a throwout bearing that rides on the transmission's input shaft, and is held in place by two "fingers", or a slot in the the bearing fork. Is there some sort of a separate holder for the throwout bearing?

Sorry if the answers are obvious, but this is new to me.

Thanks...

Chris

"Indexing" is a way of self centering. When I use this in context with a transmission and a bellhousing... The hole in the bellhousing has to be the same size as the base of the bearing retainer. The 2 are machined for a tight fit to center the transmission. The 4 bolts that hold the transmission to the bellhousing are not enough to guarantee a perfect centerering of the transmission. Those bolts hold the transmission to the bellhousing once it has been centered by lingning up the circular base of the bearing retainer with the hole in the bellhousing.

I know what you are thinking... what centers the bellhousing to the engine block?

That is usually done with the aid of 2 aligning dowels which locate the bellhousing to the engine before the bolts are tightened.



The transmission "bearing retainer" is the "hat" that is usually held on by 4 bolts to the front of the transmission. This protects the input shaft. The throwout bearing rides on the snout of the bearing retainer, not on the input shaft.

Look at the pictures of the different transmissions on the Novak site.

http://www.novak-adapt.com/knowledge/sm420.htm

Just behind the clutch splines is the bearing retainer. the long skinny part is what the throwout bearing rideds on. Behind the long skinny part is the indexing circle. On the sm420 and many other gm transmissions that circle is 4.686 inches.

The sm465 replaced the sm420 and was indexed to 5.125 inches. The bellhousings for a sm420 and a sm465 are virtually identical, but the sm465 bellhousing will have a larger diameter hole to accomodate the larger diameter of the sm465 transmission bearing retainer.