Transmission Dilemma

[crustysarge]

The TH350 in the 72 has been leaking pretty bad, looks like the front seal. Also does not like to go into gear when cold unless you rev her up a bit. Shifts and runs good once warm.

I have to decide what to do and hear are my options being in Italy:

1. Yank the tranny and rebuild myself. Never done one but I am pretty good with a wrench and micrometer. Unless some odd tool prevents me from doing so. What could be the issue here, pump and seal? If I can avoid busting open the whole thing that would be good.

2. Buy a rebuilt 350 and have it drop shipped in Dallas since a friend has a shipping container leaving soon.

3. Buy a 700R4 and do the above.

I drove the truck around 3,000 miles last year and about half was around town. Don't know that the 700 would be a super plus since I don't use a lot. I see some are only $250 or so more than a TH350.

Thoughts/opinions?

[ChevLoRay]

If it has a 350TH, I believe you can swap in a 700R4. Drive shaft length is supposed to be the same. If it is a 400TH, the driveshaft lengths will be different.

Issue then is the work that has to be done to make the 700 shift properly.

With that said, I'd go with another 350, merely to make it a bolt-in proposition. But it's all up to you. With gas prices being what they are, you are paying more than we are, stateside.

Dova, a member from Arkansas, is having his 350 replaced with a 700, by an acquaintance who has a transmission shop. The owner of the shop is the one who told me what he could do for the money and that it would be a turn-key job, including the wiring and adjustments to get it right.

[WorkinLonghorn]

Assuming the fluid level is good when you have cold start problems, I would guess that the internal seals are hardened/cracked (leaking).
A front seal leak,IF you have ruled out pan leak,requires removal of trans.
I am assuming that it is a high-milage/age unit. What does the fluid look/smell like?
Getting one shipped to you would be good assuming that it is done correctly and it actually works when installed.Remember that you will need either a new or at least flushed-out torque converter too.
Isn't there a local shop that could do the rebuild,or is a 350 considered exotic over there?
You could do it yourself but a parts cleaner and air-compresser and a few special tools really help.Cleanliness is vital as is a complete kit and any replacement hard-parts that you find are shot upon inspection.

[Longhorn Man]

a 70R4 is NOT a direct bolt in as implied above. You'll need to cut the driveshaft, ($$) replace the yoke ($$) get a lock up converter kit ($$$$) and the TV cable and HIGHLY recomended kit to adjust it properly($$$$) so it would cost you quite a bit to install the 700 in there. Relocating the X-member is easy, but more work ($$$ if you have someone else do it)
Tranny work is not too hard from what I hear... but honestly, I would still opt for a replacement. If you get one ball in the wrong place or any other little mistake, you'll be doing it again, at the cost of more gaskets and any other parts (snap rings?) that couldn't be reused... then you are down more money, and more time for overseas shipment.
I'd just take advantage of the container headed this way and get a TH350 tossed in there.

[crustysarge]

Nobody here that I know or trust to do the rebuild. I have parts cleaner, compressor, stainless steel bench etc...

I changed the filter and fluid and for sure the leak is not from the pan. Another issue I forgot to mention is the shifter linkage (internal) does not like to "notch" and stay in Park. I have confirmed it is internal where the pawl is.

Yeah, I think the rebuilt 350 w/converter is the cheapest, easiest option. The 700 sounds good but not driving much on the highway kind of defeats the purpose and extra $$$. I could then tear down the one from the truck at my leisure.

Anybody have a recommendation for a transmission place that ships or maybe in the DFW area? I see a few on Ebay that have solid feedback.

Here is one:

http://cgi.ebay.com/ebaymotors/TURBO...mZ360007728024

[WorkinLonghorn]

Sarge,read this thread;
http://www.67-72chevytrucks.com/vboa.../t-242257.html
If I was doing one myself,I sure would feel better having an extra core or a parts source that was local. Do you think there may be parts around there?

[crustysarge]

Interesting read, thanks. I am going with simple R&R and buying a 350. Anybody know of a shop or builder on the DFW area?

[Wrenchbender Ret]

Sending it that far I would go with one of the big reman outfits that test them. I imagine Jaspers has a warehouse in that area. Certified trans is big around the K.C. Omaha area. Or a Goodwrench from one of the G.M. Goodwrench suppliers.

[DavesRide]

If you do go with a Goodwrench rebuilt tranny they have a pretty good warranty. As far as rebuilding or repairing, There are two seals on the front that can leak. The seal that the torque convertor spins in and the front pump seal which requires a bit of disassembly to get it out. If it is the front pump seal it is not hard but it isn't simple by any means without proper knowlege. I would go with the replacement also. David

[ChevLoRay]

[QUOTE=Longhorn Man;2508383]a 70R4 is NOT a direct bolt in as implied above. You'll need to cut the driveshaft, ($$) replace the yoke ($$) get a lock up converter kit ($$$$) and the TV cable and HIGHLY recomended kit to adjust it properly($$$$) so it would cost you quite a bit to install the 700 in there. Relocating the X-member is easy, but more work ($$$ if you have someone else do it)QUOTE]

Longhorn Man....if replacing my TH400, a 700R4 is NOT a direct bolt-in, and does require driveshaft work. But my buddy, who has a shop, says that the TH350 and the 700R4 are the same length, and the driveshaft length is the same. Anyway, I was just quoting him.....I haven't done the physical work so I can't swear on a Bible that it is Gospel. But going to a 700R4 does indeed involve additional work and you are right about it or the transmission will not live very long even if you got it to work at all, which is highly doubtful.

For this case, I'd stay with the same transmission type especially because he's overseas. A good rebuilder like Jasper is a good recommendation. There's probably people overseas who could build it, too. After all, we have people who build foreign drivetrain components here.

[crustysarge]

Warranty won't help me much, can't really take it back!! I can rebuild it but don't have the time right now. I really would like to know what is causing the cold no shift, internal seal?

Anybody have a slaes point for the Goodwrench units? Any sponsors?

[WorkinLonghorn]

I really would like to know what is causing the cold no shift, internal seal?

That's it. Over time they get hard and even crack and there are so many in a complex hydraulic system.They sell products which claim to "soften" these seals but any improvement would be very temporary at best IMO.I don't remember an instance of this stuff actually working,but it may be worth a try,considering where you are.