700 R4 ??

[lugnut]

I have been looking at Suburbans and as we all know the rust bug has gotten to the older ones real bad so I have been looking more at the late 80s to 91. My only problem with them is the 700 I have never owned a truck with the 700 all mine had the 350 or 400. I have heard all the storys about how the 700 is crap and I know pushing around a 6000 lbs Suburban aint easy life for a trany. So is the 700 realy crap or did it just get a bad rap. I looked at one this week the first thing the guy said was The trany is slipping bad. ( He said it was not slipping till he got the rollback stuck up to the frame and tryed to pull it out with the sub /forums/images/graemlins/doah.gif) So just like any other trany you can burn it up but how long will they usaly run if you dont do anything dumb ? Were ther good years and bad years for the 700 ? Other than burnt fluid is there any thing else to look for on these. Did 91 bring any changes or just a new name for an old trany ? Can you tell 700 from the 4whatever they called it by looking ?

Thanks, Allen

 

[tin man]

I don't know if there are good or bad years. I had a 700 in my 85 blazer. It worked well for about 5 years after I bought the truck. I had an upgraded side cirvo installed at 90,000 miles. I had to have the tranny rebuilt at about 140,000 miles. I had heard the stories as well, but didn't give them any weight. All was good until I was towing a trailer on my way to Arizona. I was going up a grade when the tranny started to slip bad. I pulled over and shut down the truck in time to find out that the tranny had shot fluid onto the exhaust, which then ignited. My truck proceded to burn. I learned two lessons that night. ALWAYS carry a fire extinguisher, and never trust a TH700R4. /forums/images/graemlins/mad.gif /forums/images/graemlins/mad.gif

 

[big83chevy4x4]

the 700r4 has a square pan with 16 bolts.

the later year you get the better it is, the early ones were very weak and broke often.

there is nothing wrong with a properly maintained 700r4.

as for the tranny fluid on exhaust and the truck burnt, the vent line was plugged. it got hot and the fluid expanded and went out the dipstick tube.

 

[rjfguitar]

The original 82-84 700's are crap. 85-86 are a little better. i wouldn't worry a lot though because none of those early trannies are still original (unless you find a very rare bird with low low miles) and have probably been upgraded. In 87 they got fairly better and basically any 87 and later th700 is a decent tranny. Yes, the 4l60 is exactly the same, not the 4l60E though. My 85 700 was rebuilt with the post 87 parts by the PO and I beat the crap out of it and only had it gone through completely because I wanted a built tranny, didn't want to wonder when it was going to go, and wanted to get the most power to the ground with my new motor. Everyone has their opinion and stories about how good and bad 700's are and you bascially have to find out yourself. I would bet that one with the later model parts in good shape that stays cool should deliver lots of trouble free miles.

 

[tin man]

The front main seal gave out. I even had a brand new B&M tranny cooler. Maybe it was just really bad luck, but I won't own another one.

 

[zx672]

Front main seal gave out on mine too. Happened before I even lifted my 84 K5. When I get my 4L80e you can have my 700R4 /forums/images/graemlins/grin.gif

 

[lugnut]

Thanks for the replys guys. Sounds about like anthing else you buy used Pay your money and spin the wheel.

 

[jwduke]

The one in my '87 took a crap (Wanted to go into 1st & reverse at the same time), the guy who overhauled mine, put Corvette clutches & servo in mine. I have beat the crud out of it and it still is working good. Put the biggest cooler you can buy on it, and you shouldn't have a lot of problems. As Bobby said, try and find a '87 or newer on. GM finally pulled their head out of their arses, and got it right.

 

[hawkeye649]

[ QUOTE ]
try and find a '87 or newer on. GM finally pulled their head out of their arses, and got it right.

[/ QUOTE ]

4l60e has the exact same problems as the th700r4, because it's the same trans!! little 2 no improvements. /forums/images/graemlins/eek.gif

 

[dyeager535]

No, '87 ups use an entirely different casting. GM most certainly did make many, MANY improvements on the 700/4L60/4L60E. The casting is just an easy major change to point out.

Buddy has been towing about 6000lbs in OD, every racing weekend, with his early 90's half ton extended cab, absolutely stock, and has had NO problems with it.

I'm not saying it's a great tranny, the 4L80E wouldn't exist if the 4L60E could do everything, but a 1991 700 is so much better than a 1982 700 its not funny.