Is an 85 700r4 a good transmission?

[rs74]

I thought the early 700's were not very good. I have one out of an 85 1/2 ton 4x4 that I want to put behind a tbi 454 in K30 dually. If they were not very good then what needs to be updated to make it a strong trans.

[Fairlane514]

Apparently 87 and later are the better ones. I have visited Monster Transmission website and found some good information.

[rs74]

Can I update the 85 trans to make it a keeper. If so then what needs to be changed in it. Or better yet is there a 4L80 that I can look for out of something. That would be a better transmission over the 700r4 wouldn't it. I just want an overdrive behind the 454.

[Fairlane514]

I would consult Monster Transmission, I believe you can improve the 85. 

[rs74]

I will look them up.

[DnStClr]

The 4L80e is a strong electronically controlled tranny. You'd have to buy an aftermarket controller. But it's built as an upgraded TH400, which ( I think) the K30 had as oe because of its strength. If you're going with the big block and keep the 700R4 for the overdrive, an upgrade is a good idea.

[colton hicks]

If you want to use the 700 go with a heavy duty rebuild kit. Comes with a lot of what you'd need for a higher horsepower engine mainly better clutches. I've seen a lot of the 700 separator plates with check balls that wallow out the holes they use to control fluid so maybe even an aftermarket separator plate.
    You'll probably want a torque convertor with a higher stall rating also. A good transgo shift kit wouldn't hurt either.
       

[Captkaos]

The 1987 up 700R4's will take all 4L60 updates/upgrades and some 4L60E upgrades (minus electronics)  The pre 87's won't take all of these upgrades for strength, if you have a local builder see if you can swap out cores, if you need a core, get the 'K' 4x4 designated case as it is for 4x4s and has a stronger bell.

4L80E's is going to cost you serious bucks on top of the controller and wiring.

You only want a stall if the cam calls for one.

[rs74]

Yeah this 454 is bone stock. I will see if I can find an 87 or newer 700r4. I know the overdrive won't help a bunch with the 454 but every little bit helps.