e4od vs c6 on 7.3 idi?????

LCAM-01XA

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Not to hijack the thread, but what RPM's does yours run at when your at 60, 70 mph? Im in the process of replacing an E4OD but havent decided if Im going to go with a rebuild, or a "new" one from a local yard with a 90 day warranty

Ah, shoot what was it, 1900rpms at 55mph, 2000 at 60? Something like that... 70mph, heck, been several months now since she went that fast, so honestly I don't recall, but the 2300 number comes to mind... Assuming tach actually reads correct, vehicle speed I got GPS to verify with, but engine speed, well that's at the mercy of at this point over 20-y-o electric parts.
 

Revelstoke

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I did a great deal of researd, as I have the 88', 7.3 liter, C6. To convert, it seemed simple enough, but I really estimate it to be about $6500. Doing your own work would shave a lot off of that, but plenty of time and somewhere to work on it. To convert:

Bauman computer (an absolute must). A BUILT E40D. Sun Coast, BTS would be good options. Be sure to build it to 97' specs. The torque converter was a lot of added cost too A good TC for an E4OD would have been between $800 and $1,000. Others may claim to find them cheaper, but why risk such a large investment with a cheap TC? BTS includes one with his E4OD. Last year the quote was $4,500.

. All in all, a great project. David85 (I think that's his handle...you probably saw his posts pop up when you searched this forum) did it with great success apparently. I decided to rebuild my C6. I put in new planetarys, an R servo, Manual valve body, and Torington Bearings. I really wanted a steel caged gear set, as the C6 was all aluminum. To do this, the E4OD, I'm told, would work. My tranny guy has done it. He claimed there was too much difference between 2nd and 3rd gear, and it may over stress my tranny. I agreed and went with the stock, C6 gear set. One thing I realized though...I am putting in a gear splitter (Gear Vendors)...so, I wondered it splitting the gear might have smoothed out the difference from 2nd to 3rd, and compensated for the steep shift. Just thoughts...still wondering. One think Hughes suggested, and if I had the time, I would do is cryo-temper the aluminum gear set. This is supposed to make a substantial difference in any metalurgy, and is well worth the time if it fortifies the aluminum and/or steel as some claim it does.

One of my problems is overheating. I was pulling my D2 Caterpillar up a grade. Went from 1200 above sea level, to 4,310 in about 20 miles. I had to stop. I have a TCI, 28,000, fin and tube cooler with accompanying fan. It was not enough; even in series with my new, aluminum radiator. I have a stacked plate cooler and fan which I'm putting on now, but when it's cold out, I'm wondering how to get my tranny up to temp. Fluid shear with the C6 is a problem, and I would certainly suggest synthetic tranny fluid if you plan to climb and pull loads. Gotta say the N/A, 7.3 sure held it's own on that pull.
 

FORDF250HDXLT

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Revelstoke

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Yup, I did get a Derale, and a new grille. It's an aluminum, billet grille, and should provide much more room up front, as this new unit is 5+ inches thick. Gonna take some fabricating, but it'll be worth it.
 

Ataylor

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I have a newly rebuilt C6 in my 1987 F350. I was planning on adding a Tru-cool max 47391 in front of the radiator and then a Derale fan cooler under the cab somewhere. This truck will be towing a 28ft 5th wheel most of the time. Is it possible to over cool the trans oil. I have read that if the oil doesn't ever get warm enough, condensation can develop inside the transmission.

Revelstoke, is the trans fluid shear in the C6 that you mentioned from being overheated or too cool?

Thanks,
Archie
 

Revelstoke

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I comes from a mechanical action in the torque converter. I also build a LOT of heat on climbs. Mind you, all my climbs are a minimum of 4000+, usually 5000+ to get anywhere, so I'm climbing 20 miles any direction I go.
 

icanfixall

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Id do a zf over an e4od iv had nothin but problems out of mine

The E4OD has some areas that require attention. There are 6 electrical connections that must be clean to operate the trans. The tach sender must work properly too. There must be a heat shield on the passenger side of the trans to keep the main plug cool from the exhaust pipe heat. Depending on what year rig you have there is a speed sender either in the end of the speedo cable or the differantial that must be working too. Then the tps on the injection pump must be set correctly. Generally the voltage at idle is found to be 1.2 volts for a firm shift but can be as low as .96 volts. That will cause a very soft shift. Not what most want. At wide open throttle the tps voltage must not reach 5 volts. If it does the trans goes into limp home mode and shifts very break neck hard. You wont be driving it too long that way because the trans will fail. Its a safety design to get you home or off the road. Not drive around town getting beer or "stuff"...:eek:LOL
 

homelessduck

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A C6 with a Gear Vendor might do ok.

X2 ! That is what I wish I did .. I have grown to hate my e4od and I haven't even driven the truck yet ! I'm hoping it will surprise me once I actually get to drive it .
 

greg_a_morton

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I like my c6 with gear vendor but I would love to have the lockup. I cant get my c6 to shift right no matter how I set the vacuum screw or adjust the vacumm sensor thing on the pump. I have a long lokar shifter and shift like I have a manual valve body.
 

FORDF250HDXLT

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A C6 with a Gear Vendor might do ok.

yeah,if fuel was $1.50-$2.00 per gallon,probably it would be really.
now with $4 per gallon,you really need that direct lock up between engine and trans though.
 
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