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998 vs 727

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billd View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 7:44am
Originally posted by DaemonForce DaemonForce wrote:

 So it's definitely going to come out of either an Eagle or Hornet wagon somewhere in that PA/NY area. There's just one critical flaw with that. There are two things that put these old cars in the yards: A junk ignition system and the transmission. Since an 85 Eagle wagon has been sitting in the Pittsburgh U Pull since the middle of last month, you might want to think about going out there. Row52 has a good photo of it with the engine still in one piece so it might be fine.

One more thing. I've done crazier drives out to mislabeled "auto" Eagles with the 2CCCN vin just to grab a T-5 so you are potentially fighting the possibility that someone may have manual swapped it like I did with my 2CCCK vin Eagle. Flip a coin and call first.


It's amazing how little AMC folks know of Eagles........... people keep saying "use one out of an Eagle"
NO you can't. The case is DIFFERENT because the car is FOUR WHEEL DRIVE and has a TRANSFER CASE that bolts DIRECTLY to the end of the transmission.
The case is AMC designed for that purpose.

Junk ignition systems? LOL - you hate everything AMC, don't you? it's a FORD system identical to every single car Ford produced in the late 70s and 1980s. I made a living on cars for years - and honestly saw no more AMC or Ford products dragged in due to ignition than I did MOPAR or Chevrolet. They all had their issues back then. It was the early days of electronic conrols.

Junk transmission? If that were the case then almost all Chrysler products would be there, too and people would be throwing the MOPAR transmissions away instead of still using them - like I am......
You hate AMCs and yet hang out here - maybe you are here to spread your hate?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mopar_guy Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 8:11am
Originally posted by Hurst390 Hurst390 wrote:

They make a bolt I sprag. I cant think of a reason that the sprag area would make the case unusable.

I had the same thought. My guess is that the sprag spun in the case from what he's saying, "It is pretty scored". There's no reason the rebuilder couldn't put a bolt-in sprag in it and save what he has. A good HD convertor is a must - not just some rebuilt unit.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 8:50am
I want to clarify my earlier messages on Eagle transmissions - they used totally different output shafts and tail housings. You could use the base housing but keep in mind the Eagle used lock-up converters and the tail was totally different. 
The tail housing that bolts on is meant for transfer case. The t-case bolts directly to the extension housing of an Eagle transmission.
The output shaft is totally different. It splines to a transfer case - directly.
The transmission used a lock-up converter. Your car did not
Only the front end would be similar and with the lock-up vs. non-lock-up converter, you may run into other differences as well as far as design.

You can't use an Eagle transmission directly. The back ends are totally different.
The front would be the same as a 2wd car with lock-up converter.
So beware - investigate thoroughly before assuming. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 9:01am
Originally posted by billd billd wrote:

I want to clarify my earlier messages on Eagle transmissions - they used totally different output shafts and tail housings. You could use the base housing but keep in mind the Eagle used lock-up converters and the tail was totally different. 
The tail housing that bolts on is meant for transfer case. The t-case bolts directly to the extension housing of an Eagle transmission.
The output shaft is totally different. It splines to a transfer case - directly.
The transmission used a lock-up converter. Your car did not
Only the front end would be similar and with the lock-up vs. non-lock-up converter, you may run into other differences as well as far as design.

You can't use an Eagle transmission directly. The back ends are totally different.
The front would be the same as a 2wd car with lock-up converter.
So beware - investigate thoroughly before assuming. 
so you can convert a eagle 998 to 2wd by using the 2wd transmission parts meaning the output shaft and tailhousing? That makes more sense. The case isn't any different.? I had an eagle, but I left the trans in it when I scrapped it.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 9:24am
Some things will vary due to the lock-up converter being used by AMC in the early Eagles - I believe up through 1984. But if you wanted to convert an Eagle transmission to 2wd that should work out.
In other words, I'd not use the Eagle parts for a transmission, I'd use non-Eagle parts to convert the Eagle transmission over.
I'll have to dig into my books and my transmissions sitting on a shelf to verify a couple of things but that should be doable.

In any case, BOLT that one-way clutch in, don't rely on the splines to hold it into the case. That's the weak spot. There have been many hundreds converted to bolt-in one-way clutches over the years.
(a sprag clutch is simply a different design one-way clutch. Instead of round rollers it has odd shaped pieces more like a figure 8. So if the rollers are round like a roller bearing with ramps, it's NOT a sprag. Both are one-way clutches, or over-running clutches, but the sprag is a very specific design. If there are round rollers, it's not a sprag.)
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 1970390amx Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 2:31pm
The 998 low roller clutch outer race is riveted to the case, no need for bolt in roller clutch. I am sure what the original post is about is that the inner race has dug a round slot were it spins against the rear of the case. All cases are the same as for as lock up or not. The valve body, stator support and input shaft is what changed. An eagle CORE cold have a lot of parts in it that are better than his original trans.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 4:35pm
The 727 is what uses a bolt in sprag. The stock set up is held in by one little Allen screw. That's a weak link in the 727. The 904-998 doesn't have that issue. 1970390AMX is correct.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WesternRed Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 6:40pm
Bolt in Sprag for 904:


Sometimes you have to fix stuff, it's not like the old days where you can just go to the wrecking yard and get another one.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 8:26pm
Originally posted by purple72Gremlin purple72Gremlin wrote:

The 727 is what uses a bolt in sprag. The stock set up is held in by one little Allen screw. That's a weak link in the 727. The 904-998 doesn't have that issue. 1970390AMX is correct.


Yeah, that's right. I had forgotten.
However, the 998 doesn't use a sprag, it's a simple overrunning clutch. There's a difference. 
The overrunning clutch as used in the 998 has round rollers - a sprag uses oddly shaped pieces.
People keep calling it a sprag like every adjustable wrench is called a Crescent wrench.

The sprag is a specific design - similar but more positive lock. A true sprag doesn't have the round rollers that when you lay them on the bench they roll away onto the floor. Sprag clutch pieces can't roll.
So now that that's cleared up............ It's still a design where the overrunning clutch parts can be damaged badly - the rollers can get flattened and the race ramps worn to where it doesn't hold well. 
Sprag clutch design is less prone to that, more positive a lock. also more expensive would be my guess.

I'll have to dig into one of the Eagle transmissions I have on the shelf because although I know the control is a lockup module on the valve body and the fluid to lock things up goes to the reaction shaft support (part of the pump) the case has to be drilled for that fluid passage. it's not like a BW that has tubes. The VB bolts to the case and the signal goes through the case into the pump and out the reaction shaft support to the converter to lock it up. 
So although I've not tried this - you could likely use a lockup type case on a non-lockup transmission you can't use a non-lockup transmission case on one with the lockup module and converter - the pressure can't get into the converter without a hole in the case to carry the fluid. 

Anyway, the Eagle automatics "around here" are typically in WORSE shape than others - at least in our area.
They got burned, they got used, people used those cars hard in the winter. 
I figure around here you have a 50-50 shot or worse at getting a decent transmission out of an Eagle.
People used them in the winter and got them stuck, rocked the cars, abused them with BLADES and yes I said blades, mounted on the front. 
They also pushed around a HEAVY car. I think the SX4 is something like 3200 pounds (and that's a two door with a six) and the wagon heavier.
That being said, the case should be ok but the rest maybe not.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote DaemonForce Quote  Post ReplyReply Direct Link To This Post Posted: Feb/24/2018 at 9:36pm
Originally posted by 1970390amx 1970390amx wrote:

All cases are the same as for as lock up or not. The valve body, stator support and input shaft is what changed. An eagle CORE cold have a lot of parts in it that are better than his original trans.

Oh look, this guy knows. Clap

I've seen people convert this transmission from 2WD to 4WD on more than one occasion so I'm sure the reverse is possible starting with an Eagle core. The Eagle case is a superior 998 casting but in my luck I have only found BAD cores similar to the OP's problem here. Sprague has never been my issue but the valve body is a headache. Use the Eagle trans case and maybe some internals but mainly use the donor case. That's the entire point of the swap. It's work and still a massive coin flip, usually effected by miles and where you find it, so pay attention. I wouldn't waste any more time with it than I have already but in this case it's either pick up an Eagle core, spend a TON of $$$$ trying to replace it with another inferior 998, play the waiting game or swap in a 727. Tough choice. Not. Come to think of it I've rarely seen these swaps done to the 727 but they still happen. No idea why.
Originally posted by billd billd wrote:

Junk ignition systems? LOL - you hate everything AMC, don't you? it's a FORD system identical to every single car Ford produced in the late 70s and 1980s.

The Ford ignition system is an iron plague. Every AMC owner I've ever met drastically changed their factory ignition system or suffered. Oddly, the engine side of the ignition system hasn't been my problem so much as common failure parts like the OEM SSI module and factory switches. These reveal to be symptoms of much bigger problems, like the control wiring for the dash. That's not a Ford issue, it's all AMC/Jeep poor wiring practices. I didn't even discover this until a month ago and I get to fix it this weekend. Thank God I didn't buy many of the crap female Packard terminals shipped by NAPA. Those are flat out $1/pc overpriced garbage. Brass plated 1599C for the win.
Originally posted by billd billd wrote:

Junk transmission? If that were the case then almost all Chrysler products would be there

You ever hear the phrase leave it where you found it? Ever crawl under a yard Jeep? Tell me what you see. The Chrysler automatic is the bane of every AMC ever. between the two I'd rather have the early BW auto or literally anything else. I would even consider the TH and I actually hate that thing. I replaced the 998 with a T-5 and haven't looked back. The only possible evolution from here is the AX-15 but I'll never find one.
 
Originally posted by billd billd wrote:

Some things will vary due to the lock-up converter being used by AMC in the early Eagles - I believe up through 1984.

Wait what? Usually I find early AMCs that didn't have the lockup system until 1984. Somehow my 1983 wagon was the exception to this and it is the only pre-1984 I've ever found to come out of Brampton. Why?
Originally posted by purple72Gremlin purple72Gremlin wrote:

so you can convert a eagle 998 to 2wd by using the 2wd transmission parts meaning the output shaft and tailhousing? That makes more sense. The case isn't any different.? I had an eagle, but I left the trans in it when I scrapped it.

A buddy of mine did the 2WD conversion to his Eagle 998 and scrapped the car to make his Hornet move again. It sounds dumb but I'm sure he had good reasons. It worked out but his Hornet ended up in the scrapyard a year later and I never asked him about it. The Eagle 998 case is resilient but all of mine have been junk. The one I have left doesn't have a home and is rotting away in one of my trailers.
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