Does anyone use Gear Venders unit with TH350?

[mrghostwalker]

I was thinking of replacing my TH350 with a 700r4, in order to make my truck more highway friendly. Since the TH350 is a stronger transmission, I may install a Gear Venders overdrive unit instead.
Can anyone share they're experience with the install?
My truck is an 83 K20 with a carbureted 350, 4 inch lift and 33 inch tires. Aside from replacing the tail of the transmission, shortening the drive shaft and installing a switch, what else needs to be done?

 

[Camar068]

Link below for th350 and 700r4/4l60 gearing change, do your research though. If I had a th350 and I was going to spend the big money on the gear vendor, I'd at least consider going 700r4/4l60 as well to see if there's any benefit. What you want might be as simple as a 700r4/4l60 and gear change in the front/rear.

Look at all your options and how much you want to spend for what you want to do with your vehicle. 33's in my area (hilly/mountains) I'd go at least 4.10 if not another step.

ATI TH350

Sonnax 700r4/4l60/4l60-E

 

[Camar068]

Another option might be the 6l80/90e trans with an external controller for the trans. lol just go ahead and start a spreadsheet with total prices for all options and pro's/cons.

 

[Bennyt]

I'd probably add the 700r4 and skip the GV based on your concern about highway driving. It should be cheaper and easier.

If you were towing regularly, then I'd go with a GV where you can take advantage of splitting and OD.

I have a 700r4 in my '90 and have plans to add a GV so I can split going up grades and have 2 OD's with one allowing me to tow in.

 

[Matt69olds]

Unless you really plan to beat on the truck, or add a bunch of power, go with a 700. Properly built, I wouldn’t hesitate using one behind a mild big block.

If you do plan to add a bunch of power, go with a 4L80. It will take far more abuse that a 700 ever will, and even with the added cost of the controller it will be cheaper than a GV.

 

[StickyLifter]

I been running a Gear Vendors unit on a TH400 in my Nova for over 15 years. I haven't had any issues with it. I haven't looked at the new ones for a long time so I don't know how they operate. Mine came with the ability to have it shift automatically or manually. I have only tried the automatic mode a few times and felt like it shifted too early. It shifts very hard, almost too hard. I have received good support from them.

I'm putting in a new crate motor an transmission in my Nova (waiting on the engine from Blue Print Engines) and chose to go with a new TH400 from B&M with my Gear Vendors unit over a 700.

 

[Rickf]

I put together a '54 GMC 1 ton flatbed with a 302 inline six from an M211, TH400, GV overdrive and 14 bolt with 4.10's 15 to 20 years ago. I do not put more than 5k miles per year on it, and not a lot of highway speeds. The GV I used needs no TPS or ECM input, not sure about newer units. I ruled out the 700r4, because of past issues with several different vehicles and a 4l60 or 4l80 were not available at that time. I would not hesitate to use the TH400 with a GV again, that being said I recently put another 302 in a '37 GMC this time with a 4L80e and a stand alone controller.

 

[SquareRoot]

$3000 for a GV behind a th350 with a non-lockup converter in a K20? I'll pass. I'd go for a 4180 package at this point. Buy once-cry once.

 

[RanchWelder]

I have no experience with them yet, and I'm interested in owning one.

Keep it simple, sounds good to me.

Beef up a TH350 with hard parts, no electronics, no lock up and add the gear vendors, might be good for a long time? Weight vs tire size @ HP/TQ...
Lil' bit of math...

Not destroying one by rupturing a sub standard U-Joint probably goes a long way though...

You might want to call GV first and see if the TH350 you have needs to be modified, for what your expected HP will be. They may recommend going to a built vacuum activated TH400 or adding a booster, depending on your cam.

GV offers a final drive unit with output shaft for either the TH400 or the 4L80E, so you could go big and build the best of both world's, if you have the dosh for the 350 tail unit?

There's a TH400/4L80E GV final drive, looks to be in good shape on eBay for $1500 right now. Electric VSS Planetary set.

For what it costs to upgrade the TH350, you might be cheaper to buy a good used <$900 4L80E and have it rebuilt with the VG Planetary set, off eBay and end up around the same cash outlay, after a rebuild, as the TH350 tail shaft, by itself on an old un-built TH350... ? Guys got 97.7 feedback and his own 4x4 transmission shop...

https://www.ebay.com/itm/234555256350?hash=item369c952e1e:gBwAAOSwOLdigsUV&amdata=enc:AQAHAAAA4FpBd4b2oFqWw4EKN/Gj92Ayg3PmzFxB78kLMRYV7dfKTOcknAKvc9qw5qCcQqFawlFT4vQHAALS4awyKvCBKh72rxLTFf3tlFrrD9yXOL9OgR9WW80KfhYrCrtBOffTpS06HkUTT2jPkLD4Fq/gYibAhFD9c8BKc/1urb7WNk28NoVcXB0H1EqkCSEgwRwJrln93NGCZ4SjBNQ4SBntEAvVGu/IDuVtBpVxkMf7IIPll40fQXO+rBMC/iIf+UnRrWAVzxKShdLluMYzkHWuDtjmEAp1NEwzitffcX+ezD+y|tkp:Bk9SR_rE2IftYQ

Plus whatever you do/don't do, to control it. 4L80 can be modified to remove the "E". $900 Trans, $1500 Planetary set, few new to you Hard parts and a custom rebuild...
Possibly $3200-$3500 P/S... You'd be ahead with strength with either the 400 or the 4L80-non "E". Depends on how good of a core you start with.

Beefed up TH400 case could be thousand more, from a fresh case with hard parts. Unless he's got one laying around already? Lot's of VG parts in his eBay store... he's not too far from the VG HQ... South El Monte, CA.

I'm very interested in what either company has to say, based upon your build, so please post back.

God luck with whatever you do!

 

[SirRobyn0]

I think it all depends on what a guy wants.

Keep in mind the OP is debating TH350 W/gear vendors vs 700R4 not any of the other transmission others have mentioned, not that, that info is bad, it's just saying it's not what he asked about.

I'm not a tranny guy Matt is. I've been in the general automotive repair business for pushing 30 years. It seems like depending on who you ask the TH350 and the 700R4 are about equal in terms of strength. I think the 700 gets a bad rap, and I think 90% of that is TV cable related. Adjusted to loose and they burn up in short order, or bracketry that doesn't have the correct geometry for the cable. Also I can tell from watching my trans. temp gauge in my truck the 700, really needs a working lock-up and a big cooler if used for any heavy duty service.

So in my mind there are really only 2 huge improvements that can be made in transmission strength without installing a transmission that never came in these truck. TH400 & SM465.

My truck has the 700R4 and I had to have it rebuilt last fall. I debated on what to do. The beauty of a TH350 / 700 swap is that there is little extra work to go from one to the other. I didn't want a TH350 because I would have lost overdrive and the deep 1st gear, and it doesn't seem like it would be much more durable. So I found someone that knows the 700R4 had him build my unit to be heavy duty and I've been very happy with it.

I wouldn't hesitate to put a 700 in your truck if it was mine, with 2 caveats. You need someone that knows the 700, to rebuild it, and if you don't know how to set the TV cable up, either learn how or have your builder do it.

 

[Matt69olds]

^what he said!

Small block, mild big block, go 700. Lots of power, lots of serious abuse, bit the bullet and go 4L80.

I have a gear vendor in my Olds, it’s been in ther probably 15 years. If I had to do it over today, I’d go 4L80 without hesitation. The ability to program shift points and shift characteristics, and a lock up converter would be a huge benefit. The gear vendor is the only thing I have bid on and successfully bought on EBay. At the time, 4L80 converters and controllers were expensive, and the controllers were very primitive. Not today.

The 700 trans isn’t as bad as people think if they are built and installed correctly. You just need to find a shop that is willing to do the upgrades.

 

[mrghostwalker]

Originally I was looking to swap in a 700r4, which I've used in other trucks. The tranny expert I spoke with told me my present tranny (HT350) is stronger than the 700r4, and a better fit for my truck, since it has larger tires and I want to be able to tow with it. He told me the overdrive would be a stronger, longer lasting set-up.
I was wondering what kind of experience other people have had with that set up.