1983 k5 305 basically stock with 33 in mud terrains, needs new transmission, i will be getting the 700r4 rebuilt. is there anything i can do as far as upgrades that will help with the strain due to the tires? i didnt think 33's were really considered "oversized" when people say failure will occur (The 700R4 transmission will not last in a 4-wheel drive truck that has oversize tires, unless both rear end ratios are changed to allow for the larger tire size. You should be turning at least 2,000 RPM's at 70 miles per hour.)
i cant afford to do the gears yet but dont want to burn up a freshly rebuilt trans! is the problem be solved by a large cooler plumbed in? the trans stopped shifting into second gear about 5000 miles after the tires went on, and the truck has 100,000miles on original trans!
please help, thanks

I'm sure your are going to get told to search, but I recently did the same thing in my K5. I searched and after reading and untold number of pages about how crappy the 700r4 is supposed to be I gave up and found what I think/hope is a competent transmission shop to rebuild and upgrade my transmission. I think it was $1400 for a rebuild with a stock stall converter, shift kit to firm it up, what he called commercial clutch pack, and a corvette servo. I found cheaper places but lets just say the conversations with them were not confidence inspiring.

Its been in the truck about 5,000 miles with 4.10s and 35s. Ive been happy with it so far.

Somewhere around 100k is the life of a 700r4. I would recommend a transmission cooler if you don't have one.

Don't let anyone fool you that a 700 isn't a good trans. I have one in my Blazer with 44's and 4.56 gears. Don't believe me? Look on the cover of this month's Readers Rigs, the blue Blazer in the corner is mine. There are lots of good upgrades, but the best bet is to talk to a custom trans builder, not your local AAMCO type store. You will get what you pay for, so do some research in your area. Local speed shops, trans parts places, etc. are good places to ask for a builder, often times a good trans builder only has word of mouth advertising.

I've got a 700r4 from Bowtie Overdrives behind my 383. It's their level two tranny and I've been very pleased with it. It shifts nice and firm and has given me zero trouble since the install.

There's a couple good posts here in the last year that explain all that needs to be upgraded. You might want to read THIS POST (http://www.camaroz28.com/forums/showthread.php?t=420697) regarding failures. Good Luck.

Not much to add here, but. If you dont know of any good transmission guys. Go to a show and Shine and ask a few hot rodders... they will know. The Previous Owner of my k5 had it built some... 10-12 years ago by a local Guru. Its still in my truck today and the only problem ive had is it slips when it runs out of fluid! The weak link in a 700 is the OD..... its a 4x4, You dont need an OD!

I have a TH700R4 in a 85 3/4 ton 4WD Suburban. 35x12.50x16.5's, 3.73 gears, 6.2 diesel, NP208 T-case.

Mine is rebuild with HD clutches (both frictions & steels) 'The Beast' 3-4 Sun Shell, "corvette" aka Large servos. AT WOT in 2WD it shifts crisp enough to hurt your neck. In low range 1st gear being a 3.07 to 1 (going from memory here) is better then a TH400's 2.52 to 1. I'm in second gear in low range at anything over 5 MPH.

I have pulled trailers behind it, tow in OVERDRIVE.

A Built TH350 is weaker then a Built TH700R4.

http://www.daccoinc.com/

that's who I get my automatic transmission parts from.

Damn thanks for the quick response, florida4x4 i bookmarked that link - very helpful, all you guys posts are big help. I like the 700 with the first gear ratio, and OD, and i knew it could be built up into a stout trans. I will be upgrading it and will prolly plumb in the largest trans cooler i can find i already have a b&m deep pan that adds about 3.5 qts and i think a temp gauge might be handy. i figured it was prolly a coincidence that i had trouble soon after the tires went on, plus when u search theres so many horror stories bout trans failure cuz of larger tires,

u fellas think with the right upgrades the 700 will handle the 33's for some mild wheeling and DD'ing without the gears yet? and whats the deal i always run it in OD i dont tow with it, just hauling stuff in the back hunting camping and stuff- thanks

What gear code does your truck have?

my 700r4 lasted 257,xxx miles. we just pulled it today (toasted). i bought my burb back in 02 with 151,xxx. i then added 33's with stock gears. no problems.
i upgraded to 47s and 5.38s in 06

i'll be having mine rebuilt later this week. i'm currently running 44 & 5.38's. i have all kinds of faith in a 700r41

just my $0.02

Make sure to use the radiator cooler and a big cooler plumbed in behind that. In the ones I have torn down, they usually have forward clutches burned up. Use thin steels and frictions on your forward clutches, especially the one that's engaged in OD. This makes room for more clutches in the clutch pack = more torque capacity. Upgrade the servo that applies the band and use a late model (97+) pump from a 4L60E. They have more vanes and work better. Use a good shift kit and install a stiffer pressure regulator spring to keep mainline pressure up. Finally wire up your torque converter lock up solenoid so you can control in manually-- this gives you engine braking whenever you want.

Those are some of the things I did when I built mine to stand up to a modded cadillac northstar. That's not all you can do, but it's a good start.

shoot, I should have had you build mine then!!!

:D

thanks for the help i am definately gonna put a oil cooler in after the rad, what s the best fluid to use after its all rebuilt?

lots of different opinions on fluid.

I would suggest ATF.

fawkin sweet wasnt sure bout that

lots of different opinions on fluid.

I would suggest ATF.

Agreed.

I have always used regular old Dexron\mercon III. I tend to stay away from synthetics on trannys with cork pan gaskets. Synthetics tend to leak more than the standard stuff and they are lots more $. I always use what the manufacturer recommends and change it out every 30k or so.