trans advice

[SpeedyG]

what would you guys choose for your ride?
th400
700r4
or standard trans.

*edit.
could you tell me pro's and con's about each?
trying to get a understanding of what would be best. I dont really have a clear goal on what I would be running /power but any help would be appreciated.

[jocko]

As for manual vs auto - that is purely personal choice.

So, if you like to "row your own" - I highly recommend a manual 5-speed. Either a T5 with an S10 tailshaft or a Tremec TKO 500 (depends how much umph your motor's got - if it's hot-rodded at all, go with a Tremec, the T5 is only good for about 250-300 hp, tops. but if you don't drive like a maniac, it'll stand up for you).

If you like an automatic - then definitely go with a 700R4 or 2004R.

In other words, 20 years ago, a TH350/TH400 or stock 3 on the tree would have been fine with $1 per gallon of gas. But if you want to enjoy driving your truck when you're done - get SOMEthing with an overdrive gear (i.e. trans final drive less than 1:1). All TH350, 400, and "older" 3 and 4 speed manuals (Saginaws, Muncies, BW T10's, etc) have a 1:1 final ratio - which left you with the single option of fine-tuning the rear end gears for what your intended purpose was. For instance - if you wanted to drag race, you usually went with a fairly deep gear in the rear for increased acceleration - but you paid the price with high rpm at highway cruising speeds. With an o/d trans, you can have your cake and eat it too - the trans itself provides a fairly deep 1st gear ratio in most cases and the o/d (i.e. 5th gear) allows for low rpm cruising on the highway - so you can use a much more tame rear gear and still get decent mileage/decent acceleration. Then you can either just go with what you have for your rear end or then fine tune even further with the rear end if you have depper pockets. Many ways to skin the cat.

One note on the manual T5 - if you swap in an S10 T5 (as in out of an S10), the input shaft is too long and you have to compensate for it (while still making sure to provide sufficient clutch hub vs. input shaft spline engagement) - BUT if you swap in an F-body (camaro or firebird, etc) T5, the input shaft length is perfect (and higher spline count, etc) BUT the shifter location is underneath your truck's bench seat. There is also the World Class vs Non-World Class discussion as well. Only 93 S10 T5's were WC, all prior were non-WC. Conversely, most F-body T5's were WC. WC is a little stronger and has a roller bearing for the i/p shaft whereas the non-WC does not. Also note that on newer T5's that the speedo gear drive is electrical - that has to be converted also. Also be careful with mid-90's T5's (sorry, I forget the exact year that it changes) because the mounting bolt holes change over to a Ford patter (yes, even on a Chevy vehicle... strange)). Many variables with the T5 - some guys love em, some hate em, but as long as you plan it out, it's a good swap. Ideal solution (if you go the T5 route) is a WC F-body trans with an S10 tailshaft. Unless you're running buckets, you will almost absolutely need an S10 tailshaft on whatever T5 you install.

Note that the adapters can pose some challenges - must properly index the trans into the bell hsg in order to not put excess side load on the i/p shaft - so just throwin a few washers in between the trans and the bell hsg is a bad ide. It may work, but won't for long.

I'm in the middle of a T5 swap in my 66. It's been a bit painful, but am pretty excited about it. Finally ended up making my own plans for a spacer that still indexes to the bell properly and also spaces out the i/p shaft enough while maintaining sufficient clutch hub/input shaft spline engagement. More to follow over on the 60-66 forum in the near future, hopefully.

Bottom line: GO with an OVERDRIVE trans, manual or auto, and you won't regret it! They are very common these days and many, many mfgrs in the aftermarket.

Here are some threads about T5s:
http://67-72chevytrucks.com/vboard/s...d.php?t=471532
http://www.vanpeltsales.com/FH_web/t5_fivespeed.htm
http://www.flatheadv8.org/ernie/ernie-t5.htm
http://www.inliners.org/ (this link is specifically for a T5 swap into an Adv Design Chev - may have to search a bit for it though)
http://67-72chevytrucks.com/vboard/s...d.php?t=408694)
http://67-72chevytrucks.com/vboard/s...d.php?t=460796
http://67-72chevytrucks.com/vboard/s...d.php?t=408694
http://67-72chevytrucks.com/vboard/s...d.php?t=313954 (great ref thread from this forum)
http://www.carcraft.com/howto/116_06...ion/index.html

[solidaxel]

You will like the 4 speed either the 700R or if you have the means the 4l60E.
The electronic auto takes the guess work out of the gear slection and goes into OD when it is ready and the 700R you need some speed to go into OD, The manual is the same if you are above 50 mph you can use the OD. City driving has become a PITA now that I have the Auto OD I much perfer the truck with the auto trans.
The Tremac works great but 95% of my driving is in city trafic so I do not see much 55mph where I can use 5th gear.
I would go with the Automatic over drive (AOD)
My 4 paso worth!

[jimig1]

I'm going to run a 700r4 for the improved millage. I wanted to put in a manual but the wife said no she'd like to be able to dive it. Plus i already had a 700r4.

[72Mountaineer]

2004R in mine, same size as a TH350, no problems with bellhousing size and floor, better 1st and 2nd gear ratio than 700R4. But a little bit more difficult to set up, they shift on throttle position, not vacuum.

[longbike]

The 400 is much more heavy duty built and you can do amazing things with this trans if built right, but it is a 3 speed trans.

The 700R4 is a 4 speed trans but you will have to wire up the electronic lock up converter for cooling or you will burn it up at highway speeds right away!

If your not worried about fuel economy I would go with the 400.

[dicer]

The THM400 does not have a lockup converter nor an overdrive that the 700R4 does.
The old Hydramatics did lock up in 4th gear, though it was not a torqueconverter, a slushy fluid coupling. The 700R4 will give you a better chance at better fuel mileage.