Rebuilt 47RH Dies after 4 miles.

2 model years, 94 & 95 AFAIK.. Yah. It's a cummins conversion person's dream. Let's just hope someone comes out with a good stand alone controller for the 47RE.
 
Hope this isn't a derail.
At what point do builders start adding extra clutches in a performace transmission build?
 
We add an extra clutch/steel in direct and od brake in every trans build we do, the machined plates come standard in a TRE master kit.

I've been inside a few "big " trans shop transmissions and find billet shafts, triple disc converter, HD band, billet strut/anchor, billet accumulator piston, then use a stock servo, stock number of clutches and a vb with a transgo shift kit. Others I've seen using thinner clutches/steels to allow one more clutch. The one trans had over $7k investested and still had a stock servo ...I don't understand some of the shortcuts they take.
 
LAmiller said:
We add an extra clutch/steel in direct and od brake in every trans build we do, the machined plates come standard in a TRE master kit.

I've been inside a few "big " trans shop transmissions and find billet shafts, triple disc converter, HD band, billet strut/anchor, billet accumulator piston, then use a stock servo, stock number of clutches and a vb with a transgo shift kit. Others I've seen using thinner clutches/steels to allow one more clutch. The one trans had over $7k investested and still had a stock servo ...I don't understand some of the shortcuts they take.
Click to expand...



Stock servos work great if they are close to factory new condition. I upgraded the 2nd gear/intermediate servo cover with the $21 Sonnax cover with custom o-ring seal to prevent 2-3 shift bind-up issues, but other than that, I'm still running stock servos in both of my transmissions. I'm even running a cheap $20 kevlar flex band and I've had zero issues with burning the 2nd gear band. I am running the 4.2 ratio lever with elevated line pressure so it's getting a lot of clamping force, but no need for a larger aftermarket servo so far on my POS tranny build.


My problem this time around has been burning up the forward clutch. I measured the forward gear splines and they're about .68", this is enough room for (5) 0.061" clutches and (4) 0.070" steels, but it is really difficult to get the alignment just right to make sure that top friction doesn't move too far rearward and come off the splines of the forward gear.

Since I don't have access to a lathe, or buddy with a machine shop, I'm going to go back to a 100% stock (4) friction forward clutch setup and see if it will hold at my current power level. I tried to run (5) frictions the first time and the top friction moved a little too far and came off the splines of the forward gear. I tried to run 4 frictions the second time with double springs and different reaction plate thickness and ended up with the 4th friction moving too far rearward and coming off the splines leaving me with just (3) frictions engaged on the forward gear. It held for a while with three frictions, maybe 45 passes mid 12's passes at the track but it definitely was slipping.
 
Ok guys. Got the trans most the way reassembled. Got the main case put back together, and the overdrive unit most the way together.. I noticed there is basically no clearance between the top steel and the wire snap ring in the OD brake clutch. The clutch has 6 Raybestos hi energy frictions, a stepped reaction plate, and no waved snap ring, with the stock .070 flat ring. What do you guys think of this? Kinda weird. May be why my OD clutch burned up last time. (Though IIRC, it had clearance the first time around with the frictions/steels from DTT)
 
When I say "basically no clearance" it means that the wire is touching the top steel, but it's not compressing the stack.
 
deerefanatic said:
Ok guys. Got the trans most the way reassembled. Got the main case put back together, and the overdrive unit most the way together.. I noticed there is basically no clearance between the top steel and the wire snap ring in the OD brake clutch. The clutch has 6 Raybestos hi energy frictions, a stepped reaction plate, and no waved snap ring, with the stock .070 flat ring. What do you guys think of this? Kinda weird. May be why my OD clutch burned up last time. (Though IIRC, it had clearance the first time around with the frictions/steels from DTT)
Click to expand...


I have 6 Raybestos Hi frictions too and machined ( .105" ) stepped reaction plate and thinner flat ring. Top clearance was... if i remember right .060" between top steel and wire snap ring.
 
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CSnyder said:
I had this very conversation with Dave in person yesterday discussing my options for a VB rebuild on my 321K 1995 47RH. He said we can "try" to make it right but being you cant buy new RH VB's its gonna be a toss on if its right or not when installed. He said all of them that he sells are within specs when they go out but 90% of cores arent reuseable.
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what is the main reason that the cores are no longer reuseable?
 
97rada said:
what is the main reason that the cores are no longer reuseable?
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It is either that they have had a shift kit or the likes installed. The valve bores are worn and the valves bind. That is probably he most common problem with old VB's.
 
Yah, what Raychem said...

Talked to Phil @ DPC just a few minutes ago. He received my converter. Gonna check it out, clean it up, and hopefully send it back to me today... So far, so good on the customer service from Phil. :)
 
OK. Got the word from Craig down at Goerend. My valvebody passed the test on the tester! Yah! Also got the overdrive piston spacer coming for it as well.

Now, Craig told me, that as long as the wire snap ring in the overdrive section for the brake clutch is not actually compressing the clutch pack, that it's OK not to have any clearance up there as the ring is just to keep the top steel from falling out. But, what that's going to equate to is only about .060 clearance between the overdrive piston and the top steel when I get the correct piston spacer in there (which is coming from Goerend with the valvebody).

What do you guys think? The frictions are Raybestos Hi-energies, with new steels. All the steels are flat (checked em against the ways on my mill.... I know for a fact those are dead flat!) But, when I do my stackup, the top steel sits just slightly higher than the bottom of the wire snap ring groove.... Course, the wire ring is smaller than the groove is wide, but still, seems wrong. For what it's worth, the frictions themselves have a bit of a wave to them.... Craig said that's normal for OE type frictions, and it's because of that reason that it's ok not to have the excess clearance.
 
Pictures

OK guys, some pics of the overdrive unit:

First, a measurement.

The reaction plate is .215" thick at it's thickest point, and .133" in the grooved area

Reaction Plate:
IMG_0156.jpg


Reaction plate backside:
IMG_0157.jpg


Single flat snap ring installed:
IMG_0155.jpg


IMG_0154.jpg


Everything installed EXCEPT the top steel:
IMG_0152.jpg


Top steel installed:
IMG_0149.jpg


Wire snap ring installed:
IMG_0147.jpg


there you guys go..... Now watcha think?
 
Oh, and one last picture, this shows the friction with wet spots on it, proving that the clutches are indeed waived and not flat, as you can see the spots where it was and was not touching the steel.
IMG_0151.jpg
 
It's actually a 95. But yes, Auto conversion. That @#$% 5spd is laying on the shop floor right now, and it's NOT goin' back in.....

As a total side note, could you PM me with what mods you've got when you dyno'd that 538hp in August? I'm trying to guesstimate where I'm at....
 
Big Blue24 said:
Overdrive clutch pack looks fine to me.
Click to expand...

OK. Now, with the piston spacer that I measured that I need, I've only got about .050-.060 clearance between the piston and the top steel. That seems tight to me? Or will the just simply "wear in" as everything settles? My shift kit shifts into overdrive pretty firm, so any fighting between the brake & direct clutches should be brief....
 
deerefanatic said:
OK. Now, with the piston spacer that I measured that I need, I've only got about .050-.060 clearance between the piston and the top steel. That seems tight to me? Or will the just simply "wear in" as everything settles? My shift kit shifts into overdrive pretty firm, so any fighting between the brake & direct clutches should be brief....
Click to expand...

How exactly did you measure for the overdrive piston spacer, and what size did you order?

It's part 213 in this schematic: https://www.wittrans.com/Schematic.aspx?Transmission=A518/A618&Schematic=6
 
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