700R4 Rebuild - shopping list

Quickstop [UK]

Quickstop [UK]

Combating adversyty.
A friend (MDH - Syclone owner) and I are thinking of rebuilding a 700R4 over the summer. We've never done it before but figured having a spare lying around might be a good idea for him/someone else.

We have the ATSG manual and another one that I found on Amazon but I was wondering if people had some thoughts as to the parts that we will need and tools they'd recommend. I understand you can get away with a lot of improvisation but I'd prefer to get proper tools if not too expensive.

Also, I believe you could spend an awful lot of money on this within a wide range. What are the minimum recommendations people have for a rebuild with some upgrades thrown in?

The trans in question was running fine until the the ill-advised owner tried a boost launch by revving it in neutral then dropping into D. Any ideas what might be the likely cause?

first signs of trouble
Broken trans

This is probably what happened

We may have to disassemble it first to really identify the damage but if you guys have some suggestions, that would be really appreciated.

Any links to trans shops or trans rebuild threads would be really appreciated. I will as ever continue to search!

Thanks guys! :tup:
 
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bezerk

bezerk

New member
Re: 700R4 Rebuild - shopping list

does the transmission still does anything>? or completly death?
 
DaveP

DaveP

Active member
Re: 700R4 Rebuild - shopping list

Quickstop [UK] said:
The trans in question was running fine until the the ill-advised owner tried a boost launch by revving it in neutral then dropping into D. Any ideas what might be the likely cause?
Click to expand...

If it has Reverse, my guess is a shattered forward sprag race. The classic symptom of a broken fwd sprag is it will move in D3, have three gears, and if going fast enough can be shifted into D4 and 4th. But won't move from a stop in D4. D3 applies the overrun clutch, which transmits torque 'around' the busted sprag, and it can be driven.


Tools:

  • Big hose clamp to align the pump halves during reassembly.
  • Very good, strong, snap ring pliers for output shaft snap-ring. (Distort the F out of it to remove. A new one is included in the seal kit).
  • Some kind of fixture or compressor for the lo-rev piston in the rear of the case. (I made mine from some 1X1/4 flat stock and a piece of all thread).
  • A "clutch press" to do the pistons in the fwd drum. (A trans-builder friend of mine gave me an extra he had under his bench).
  • Various picks, screwdrivers and punches to do the snap rings, pick at valve body valves, and remove seals.
  • Feeler gauges to measure clutch pack clearance.
  • Air and rubber-tipped blow gun to pressure check clutches after assembly.
  • Plastic tub and two 4X4 blocks to stand it up right in on the blocks during disassembly. To contain the mess it makes.

Don't be surprised if your first attempt at a 4L60 overhaul doesn't work properly, or last very long. These are complicated, easy to get 'lost', and there's a few things to be aware of and look for, but not too fussy. Good luck.
 
Throws

Throws

Active member
Re: 700R4 Rebuild - shopping list

I'd like to try my hand at rebuilding a core... I figure there's parts I'd have to source out (teflon washers), but for the most part, I like the involvement in the process.

-P
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
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Don W.

Don W.

Stab it and steer it
Re: 700R4 Rebuild - shopping list

For some pics of the HD pieces pick up the July 2012 issue of Street Rodder mag. Not a "how to" but pics of HD parts you might consider.
 
Throws

Throws

Active member
Re: 700R4 Rebuild - shopping list

Jimmy said:
It's just gonna blow up again no matter what you put in it.

Ask me how I know.
Click to expand...

I'm game... how do you know? Geniunely want to try this sometime.... rebuilding the trans, not blowing it up.

-P
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: 700R4 Rebuild - shopping list

We dismantled the transmission this week and took a lot of photos (in this album: 700R4 disassembly) to aid reassembly but the main ones are here:

84f830bf.jpg


b26a4b2f.jpg


When we took it out, these all dropped out the pan...

ef0097f8.jpg


They were shattered as well. I think we found the culprit...

3458bbbc.jpg


DaveP said:
If it has Reverse, my guess is a shattered forward sprag race.
Click to expand...

DaveP called it - :D

There's more...

3bd7d3f6.jpg


b2bea5f8.jpg


f6183dbf.jpg


I bought some expensive Knipex snap ring pliers as recommended in one of the threads I reference above. I also bought some cheap picks from a Harbor Freight equivalent. So far, the expensive pliers were not that effective and the cheap £4.99 set was worth ten times its price.

I would recommend a strong set of straight snap pliers as well as a sturdy screwdriver for getting the larger interior snap rings from the two drum assemblies.

So far this has not been as intimidating as I thought. Obviously the assembly is the hard part but I am optimistic we can do it. I think the hardest part is knowing what things are and the names of items so you can comunicate effectively.

sprag-drum-reverse-input-clutch-press-cyclinder-apply-piston-wombat-minigun-jigger

It's fascinating to see - aside from the hydraulic logic circuitry, it's an elegant and simple design.

The clutch material on a lot of the clutches seemed to have worn down a lot as well. The oil was clean but there was obvious wear other than the catastrophic failure of the forward sprag race.

Next step - identify and order the required spares and plan the rebuild.
 
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DaveP

DaveP

Active member
Re: 700R4 Rebuild - shopping list

This is the fwd clutch piston. It is very common to find this piston cracked in any 4L60 / 60e. Some seal-kits come with a steel piston replacement. (I've never installed it. I think there are some mods required to utilize it. I'm not sure. I've never researched it). The forward clutch is applied in any range other than P, N, or Reverse. When this piston cracks, fluid pressure goes through it and applies the 2-friction Over-run clutch piston that nests in the other side of the fwd piston. . Nothing bad happens until it shifts into 4th. When in 4th, the little Over-run clutch fries very quickly. The trans still operates. The only noticeable difference is that there is no longer any engine breaking in D3, D2, or D1.

You should have found that the two small diameter Over-run clutch frictions, and the one steel were very badly burned.

If you need to know the description of some component, put up a pic. Several people here know these transmissions well enough to help you with parts ID's. Good luck.

3bd7d3f6.jpg
 
DaveP

DaveP

Active member
Re: 700R4 Rebuild - shopping list

Opening note: These transmissions are designated as "4L60". This designation was applied to them in 1990. So all 90-up transmissions of this type are 4L60. Sure it may be a matter of semantics, but the SyTy transmission was never a "700R4".

This is the fwd clutch piston. It is very common to find this piston cracked in any 4L60 / 60e. Some seal-kits come with a steel piston replacement. (I've never installed it. I think there are some mods required to utilize it. I'm not sure. I've never researched it). The forward clutch is applied in any range other than P, N, or Reverse. When this piston cracks, fluid pressure goes through it and applies the 2-friction Over-run clutch piston that nests in the other side of the fwd piston. . Nothing bad happens until it shifts into 4th. When in 4th, the little Over-run clutch fries very quickly. The trans still operates. The only noticeable difference is that there is no longer any engine breaking in D3, D2, or D1.

You should have found that the two small diameter Over-run clutch frictions, and the one steel were very badly burned.

If you need to know the description of some component, put up a pic. Several people here know these transmissions well enough to help you with parts ID's. Good luck.

3bd7d3f6.jpg
 
Ed Gasket

Ed Gasket

From England
Re: 700R4 Rebuild - shopping list

I'm certainly no expert on mine, just finished rebuilding it today - I went for a TCI servo, a 9-clutch upgrade for third, fatter band and an uprated sunshell. There was a whole bunch of other stuff I'd have liked to have upgraded, but cash was tight and it's been off the road too long already!
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: 700R4 Rebuild - shopping list

Well after much umming and aahing, we made some progress. I managed to source a replacement fwd clutch piston from 700r4l60e.com along with some other parts including the 29 sprag element and a new inner and outer race.

www.bulkpart.com sell a rebuild kit for $330 and it came with everything we needed for the rebuild. I haven't finished this yet but I was impressed with the kit apart from snap rings. The clutches were all Raybestos Z packs which was a pleasant surprise. Given the cost of this kit, I can't recommend highly enough that people do this themselves in future, at least once. It's not black magic.

The rebuild is not that hard - you just need to follow the advice in this thread:

http://www.bangshift.com/forum/showthread.php/21939-BANGshift-700R4-rebuild-tech-part-1

We did have a couple of snags -

1. Snap rings are very hard to replace. Don't lose them. I have NO idea where two of them went and they don't come as spares in the rebuild kit so that stopped us dead. It's possible that they were damaged when we got them out and we just tossed them thinking the rings would be in the new kit. They may have been damaged because the tools were unconventional.

2. The hardest bit was the check balls - despite taking LOTS of photos, it was still a hassle to get them into the right place as they seemed to fit in many places.

3. Tools - long flat head screwdrivers and the correct pliers (not the bent ones!!) make life a lot easier.

4. I'm also getting a spring compressor for the input drum.

B11A4953-2A10-49EB-A762-DA23E4B52850-10284-00001118B3D1FEDE.jpg


C90A85CB-6264-45E5-922F-4A89CBF79A66-10284-00001118C3288766.jpg


EFE3496D-CBA4-41DD-A31C-641C678035A6-10284-00001118CE4221E8.jpg


Having a clean place to work is essential.

A63BFD73-31DA-4738-8C69-A471236E1B6F-10284-00001118D9D3382D.jpg


Hopefully it'll all go back together!
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: 700R4 Rebuild - shopping list

Well, after a bit of a pause, I got round to finishing up the transmission rebuild. It will be installed in a friend's Ty soon with any luck.

There were a few challenges in reassembly but with the aid of a good book, the internet, some patience and a lot of double checking, this job was fine.

We got stuck due to some missing snap rings and I found a snap ring service pack from Amazon that saved the day. I also bought a spring compressor to do the forward clutch assembly.

I'd also recommend the Transgo spring pack - it comes with a washer to press down the spring in the forward clutch drum without warping the spring.

The Teflon seals were a real pain - I wound up using a hose clamp to compress them back down to size. Not fun with the wrong tools.

I would be happy to do this again - definitely doable at home. For the price of some of the rebuilds out there, you could have all the tools and then some and still use the decent internals.

Hope it survives the test drive!

:D

The rev/input drum was a total pig to get it to line up in the trans and settle. It finally went in but that was one of the most frustrating parts of the job.
 
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