Stude4x4

Well i don't know if its the original clutch, but I felt it slip for the first time a couple days ago. When I really get on it now, I can definitely feel it. I'm not starting another "whats the best clutch" thread. I'll figure out what to go with. What I'm wondering is how to determine what kinda power I'm putting out. I know a dyno would be the best way to tell. To make sure I get the right clutch, what kind of ball park numbers am I at with these mods?

Pump turned up all the way
Fuel pin rotated
HX35
1/16" advanced timing

Future:
Bigger injectors (nothing crazy)
Fuel pin grind
3200 gov spring
Upgraded lift pump

Truck is a daily driver with occasional towing. Another quick question and then I'm done. What about the Getrag? Do they hold up to power? Should I consider a rebuild while its out? Sorry for the long post. Thanks.

Jake

Mark Nixon

Jake,
First off, does the trans shift and act fine?
There's a couple of very simple tests I do on Getrags to determine if I'd go further than a new clutch.
With the trans sitting horizonally, take the input and push down on it, if it pushes back (pivots) it's time to be concerned.
This point is usually the end of the arguement, but you can stand it on end, check for any in and out motion on the input, if there is ANY all, then it's definitely time to rebuild.

This input wobble and play is usually the first indicators of issues that are already present, pronounced bearing wear and potential bearing damage, but if the tranny works reliably, it'll likely be a simple re-bearing, with stop rings rebuild.

Count on having to do the input, but you MIGHT not have to.

Personally, I replace the input, regardless, but it's your choice if the bearing surface looks good.

Mark.

Stude4x4

Thanks Mark,

I'll do that when it comes out. It shifts fine, syncros seem to work. Sometimes it is hard to get into reverse, but I don't know if that's just the nature of this tranny. I definitely can hear the input bearing growling when its in neutral. Thanks again.

Jake

Crossy's son

If you can afford a Southbend CON-OFE or Even an CON-FE if you never wanna worry about it hurting it.

I'd do that^^

The OFE has organic material on one side and feramic on the other which grabs amazing when it's warmed up, and the CON-FE is rated for liek 500hp and is Feramic on both sides. I've driven both and There was barely a difference in grabbiness. The CON-FE was in "Wannadiesel's" truck about 8 months ago and the OFE was in my Uncle's 99 Cummins.

I was gonna say get another stock replacement 13" sachs clutch since they're awesome but once you said anything about injectors, I think you need a clutch that's never gonna slip. Because once you slip a sachs 1 or 2 times it just gets worse, and they usually start to slip as soon as you upgrade injectors

Trebor

I always thought that 300,000 miles [300K] was the normal anticipated amount of mileage and wear of the life expectancy of our clutches.

Crossy's son

The one in the 93 had 360k when it finally started slipping in 4th and 5th, only because i had turned up the pump alot. If i had left the pump alone and my Dad and I just drove it normally like the PO did, it would have gone another 360k I think.

freight train

I personally believe anyone who gets 300k on a factory clutch is pretty lucky. My dually which came from TX had 140k on it when the release bearing started squeeling like a shot pig. It pulled a 36' living quarters horse trailer there and since I have had it have pulled my 24k eager beaver loaded several times. My truck has minor tweaks on fuel and air but nothing serious. I am a big fan of the Sachs clutch but like Crossy said once they start to slip it gets bad real quick. Another alternative is upgraded clutches from Sachs. When I ordered my last kit the guy told me that Sachs offers two other clutches made from different material. I didnt ask about price or what they were made from but if the quality is as good as whats in out trucks from the factory I would never hesitate. I just paid $410 shipped for a kit for my RC project about 6months ago. Not bad for a good kit in my opinoin. Eitherway good luck with the swap.

Mark Nixon

Here is what has been proven to me, personally:
The stock Dodge/Sachs throwout bearing and pilot bushing limit the overall mileage on these clutches.

My first 1991-1/2 1 ton had 175,000 miles on it when the T/O bearing locked up and destroyed the pressure plate fingers.
Now, given that my experience is quite possibly the average miles the THROWOUT BEARING lasts (I believe it's a high average), it's likely these trucks with over 300,000 miles have POSSIBLY already had at least a throwout bearing replaced at the LEAST.

That being said, I have personally pulled 6 or 8 trucks apart that I am pretty confident never had the CLUTCH (or pressure plate) serviced in the 250,000 to 400,000 mile trucks I have pulled apart.
Some quite plainly had already had a replacement pilot bushing.
A few even had total clutch replacements.
NONE (yes ZERO!) had an untouched transmission, even the 70,000 mile wrecked one!

The kicker is that since many of the Getrags have had warranty work, IE; usually a total replacement, they likely got a new throwout bearing and *maybe* a pilot bushing while the trucks were apart.

This was usually within the first 5,000 to 80,000 miles.

This could well be the biggest reason that people can get 300,000 plus miles out of a clutch.
I'm totally convinced that the DISK and PRESSURE PLATE will run 300,000 plus miles, however, time has proven to me that the Pilot bushing and T/O Bearing generally will not.

Remember, Dealerships are cheap, they'll tend to replace JUST what it needs to help it make warranty, if the rest "looks good enough", back together it goes and it's kicked out the door.

Mark.

Stude4x4

I agree Mark, I think that is very true. I guess a clutch good for 350 hp would be suitable for me. I'll probably call a couple companies and go from there. Where is the best place to get bearings and other parts for the getrag? I need to figure a cost so I can start to save. Thanks.

Jake

Mark Nixon

There are several companies that have good customer relations for the parts and technical advice on Getrags.
I usually buy my parts from Zumbrota in Minnesota (www.zbag.com), but I have seen good feedback for Blumenthals (spelling?) in OKC, as well.

Motive Gear also has a decent set of bearings and synchros available.

Be advised that if there are any major parts damaged, say a synchro hub, cluster pin or main shaft gear, they can be tricky to come by, but I have a source for those as used parts.
The cluster and input shaft seem to be readily available new.

One more final word of information:
MOST suppliers of bearings for these transmissions are likely going to have overseas bearings.
Finding reliable U.S. bearing sources, much less economical ones, is getting exceedingly hard.
I believe Zumbrota has offered a "Hi Cap" bearing, which seems to be a well-built bearing, but other suppliers may well have the same inventory.

Mark.