"Rebuilt" 700r4 issues

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Obwonkonobe

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Let me add, so that I'm not misunderstood. I'm not saying by NOT having lock up hooked up that the 3/4 clutch pack will burn up, or that the 2/4 band will burn up. Lack of converter lock up is NOT what causes these issues. But, heat is a problem on the 700r4 so you want to keep it as cool as possible at all times possible. The cooler and the longer you can keep it cool, the longer it's going to last. Besides an additional trans cooler, the best way to keep it cool is by locking up the converter.

For now just for simplicity since I just got it working as it is I probably won't tear back into it and hook it up. But pretty soon here I hope to stab an aditional cooler into it, does any one have any suggestions?

I have a 4 core aluminum radiator that has the built in cooler that I currently run, and then I also run an ac condenser. I figure Il use rubber lines and posutuon the cooler in the center. I have a mechanical clutch fan as well.
 

Obwonkonobe

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Great! So just to check do you feel every shift? 1-2 2-3 3-4 and maybe lockup if you have it all hooked up?
And how do the shifts feel, and are they at a good RPM range?

This is pretty much what I asked myself when I was adjusting mine by feel. well.. And after since I'm always a little paranoid about my pickup.
Yup I fell every shift pretty solidly. Im adjusting on feel right now too since I don't have my speedo hooked up yet, but if I had to say its a HAIR late and hard, but from what I've read that's not the worst issue to have, so I think Il leave it. Im also weary to do any further adjustment on feel because what I'm basing it on currently is my knowlage of how the old 350 felt, may it rest in piece(s).
 

Dutch Rutter

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https://www.summitracing.com/parts/bmm-70268 This is the cooler I went with and it does great. This company http://www.trucool.com/products/tru-cool-max makes some that I would like to eventually try just because they are so large and offer a lot of good features just like the B&M but offer many other options.

On mine I have an E-Fan wired to a button in the cab, helps a bunch in traffic. There is alot of debate on if you should run a cooler with the factory setup or just the add on cooler, It really depends. With the plate cooler I doubt there is enough room between the two radiators since the plate types are thicker but they do work much better. I ended up placing mine in front of the AC radiator.

Late and hard is alright in moderation. You don't want it running too late and hard. as it will become annoying in stop and go traffic and it will also cause the trans to get warmer then it needs to. I ended up making a mark and then small adjustments. farther in will make the shifts harder and higher RPM the farther out is softer shifts and lower RPMs.

Also I have to agree with what @HotRodPC and @4WDKC have said definitely get that lock up setup and working. It would also be wise to get a temp gauge on that trans if you don't already so its temp can be monitored and you would be able to see how the changes you make effect it.

Very glad its working better! but be very careful because it may end up burning out if it overheats.
 

Obwonkonobe

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Thank you for the suggestion, il defiantly get one thrown on it soon. Im going to weld in a drain bung when I do my first fluidchange, and Il problably use a temp sender as a plug.
 

Obwonkonobe

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https://www.summitracing.com/parts/bmm-70268 This is the cooler I went with and it does great. This company http://www.trucool.com/products/tru-cool-max makes some that I would like to eventually try just because they are so large and offer a lot of good features just like the B&M but offer many other options.

On mine I have an E-Fan wired to a button in the cab, helps a bunch in traffic. There is alot of debate on if you should run a cooler with the factory setup or just the add on cooler, It really depends. With the plate cooler I doubt there is enough room between the two radiators since the plate types are thicker but they do work much better. I ended up placing mine in front of the AC radiator.

Late and hard is alright in moderation. You don't want it running too late and hard. as it will become annoying in stop and go traffic and it will also cause the trans to get warmer then it needs to. I ended up making a mark and then small adjustments. farther in will make the shifts harder and higher RPM the farther out is softer shifts and lower RPMs.

Also I have to agree with what @HotRodPC and @4WDKC have said definitely get that lock up setup and working. It would also be wise to get a temp gauge on that trans if you don't already so its temp can be monitored and you would be able to see how the changes you make effect it.

Very glad its working better! but be very careful because it may end up burning out if it overheats.

I like your recommendation but unfortunately the swap has drained my funds. I figure il just assume its running hot (a safe assumption here in az) and use what money I can to get a cooler. I found this one on amazon that seems to work well, opinions?

https://www.amazon.com/gp/aw/d/B000C3DDKO/ref=ox_sc_act_image_1?smid=ATVPDKIKX0DER&psc=1
 

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I completely understand that, I've been there myself. Looks to be very close to the B&M so it should be fine. I can say from my experiance the plate type is much more effective then the tube and fin type, temps stayed cooler longer.

The B&M also has a low fluid pressure loss and if the fluid temp is low it will bypass the cooler automatically which is a good thing as it avoids over cooling the fluid on colder days. I'd bet that Hayden has the same features.
 

HotRodPC

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If the shift points are a hair late and a hair hard, then you've still got the cable a bit to tight. This means the pressure is a tad high which is regulated by the TV Valve also. Better a hair late and hard than early and to soft with low pressure. The low pressure is what will allow the slippage and heat generation to cook the transmission. The late and hard shifts can be hard on the hard parts, u joints and transfer case over a period of time of constantly being beat on but if it's not to terribly hard you're probably going to be OK with it as is.
 

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This may sound harsh, but this whole thread is a waste of time if there's currently no plans to get the lockup working anytime soon.

And don't drive in OD until it is functioning. Even with a big aftermarket cooler.
 

Obwonkonobe

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This may sound harsh, but this whole thread is a waste of time if there's currently no plans to get the lockup working anytime soon.

And don't drive in OD until it is functioning. Even with a big aftermarket cooler.

I understand, honestly now that its shifting right and I have plans for a cooler, im gonna leave it alone for a bit. Il contact the builder soon and ask if cracking open the pan to install lockup will void the warrantee. THANK YOU to everyone for your help, another great reminder of why this forum rules!
 

bucket

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I understand, honestly now that its shifting right and I have plans for a cooler, im gonna leave it alone for a bit. Il contact the builder soon and ask if cracking open the pan to install lockup will void the warrantee. THANK YOU to everyone for your help, another great reminder of why this forum rules!

It's normally the other way around. A non-functional lockup will void the warranty. But this guy doesn't seem to know exactly what he's doing.
 

Obwonkonobe

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It's normally the other way around. A non-functional lockup will void the warranty. But this guy doesn't seem to know exactly what he's doing.
That's the vibe I'm starting to get, considering I've never heard one bad thing on lockup
 

HotRodPC

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Yeah, As said, I lost all confidence in the builder when you said he mentioned you don't need lock up.

But what makes you think you need to remove the pan to install lock up? The builder should have had all that set up in the transmission with the build. All you have to do is wire it from the 4 prong plug on the outside of the case. And it probably doesn't 4 wires, it's just a 4 prong looking plug. Could even be a single wire.
 

Obwonkonobe

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Yeah, As said, I lost all confidence in the builder when you said he mentioned you don't need lock up.

But what makes you think you need to remove the pan to install lock up? The builder should have had all that set up in the transmission with the build. All you have to do is wire it from the 4 prong plug on the outside of the case. And it probably doesn't 4 wires, it's just a 4 prong looking plug. Could even be a single wire.
He said he "removed all that crap wiring"...
 

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I'm going to babble on for a few minutes here regarding my 700. I bought a 1984 6.2 diesel Suburban in California over 10 years ago, with a rebuilt but weak shifting 700. On a trip back from Michigan a few years ago it randomly stopped shifting, long story short, I looked on eBay and I wasn't happy with what I was reading, so a friend recommended a respected builder in South Carolina, so I told him to build me a 1984 early version 700, but he highly recommended the newer style 1985 with an auxiliary valve body, so I had him build me one with a few extra tuff parts, but keep in mind I only have an anemic 6.2 diesel. So I picked up the transmission, gave him his $900 including rebuilt TC, and it shifts rock hard. GM has a bunch of tricks up their sleeve, where they put spacers in to the clutch packs, everybody knows this, but unless you tell the builder to use all the best parts and pay a few dollars extra, it's very easy to put these stupid spacers back in and shorten the life of your transmission. I rebuilt a few transmissions over the years, and I've seen some of where the clutch packs at the beginning of the pack are in good shape, and the back of the pack is burned up. As fluid passes through, it heats up from a soft shifting transmission, which of the way GM sets up their transmissions. Fords and Chryslers always had a firmer shift from my experience. So in any case, he installed a hydraulic lock up in my transmission, as my lock ups never seem to work, and I have no experience or patience to figure out the wiring. Mine locks up hydraulically 43 mph. I wish it was a tad higher, but I don't think it's adjustable. From time to time I pull a heavy U-Haul transport trailer with a heavy American car or even a diesel truck on it, and even though I'm going up and down the mountains where I live, it still has a respectable shift. Heat is the killer of all transmissions, and tires and other things obviously.
On another note, I just drove a 1984 350 gas K5 Blazer back from San Francisco, and the guy claimed it had a rebuilt transmission, and judging by the fluid, it did. But it shifts so so smoothly and softly, it made me crazy, but I was reluctant to start tinkering with the TV cable, so I just drove it 4000 miles coast to coast. And now I can start tinkering....

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Dutch Rutter

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He said he "removed all that crap wiring"...

By the way. it is possible to check and see if the lockup is setup and working inside of the transmission without taking the pan off, wouldn't hurt to check. But this ^ really makes someone wonder what kind of builder this is. Most if not all rebuilds on any part should fully restore factory operation to the part being rebuilt. Also I for one would be pissed if a rebuilder did that without asking me first, In my mind why would I pay someone good money to ruin a transmission just so they don't have to do their job fully.
 

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