RE4R03A Transmission Rebuild Question

[cbrooks0003]

Since reverse went out in my transmission, I decided to rebuild my second ever automatic transmission. I got it apart and found that the reverse drum bushing went out and it looks like the reverse drum was wobbling so much that it cut grooves where it rides on the stator, effectivley destroying the stator too. Also, the low/reverse piston seal was blown. Amazingly, in drive, you'd never known anything was wrong except for a very slight whining that only I ever noticed. So I got a new reverse drum and have a stator (pump cover as they call it) ordered. I also got a complete kit with steels and all 5 solenoids. Also I installed the Transgo shift correction kit in the valve body. It also came with high temp sealing rings for the stator. Also got a bushing kit, a new band, and a new converter. Total spent was about $900.

So my question is, are there any tips or tricks anyone knows of that I should do while this thing is apart? I already had a transmission cooler on, but I bought the car with 90,000 miles on it, so I guess it might have been too late, although I don't see anything that would indicate this was a heat problem... more like an oiling problem due to low pressure from the failed seal. Plus the whining has been going on for 40,000 miles, so I'm sure I was hearing a pressure leak all that time. Like I said, this is only the second automatic I've ever done, so even obvious things will help... right now all the components are done and waiting for the new pump cover in order to put it back together...

Thanks!

[elwesso]

Honestly you're about 29 steps above most people here. I'm not sure of anyone here that has rebuilt their own trans. I'm assuming you have the factory service manual, it's got a great section on rebuilding the trans. If not, go to http://www.nicoclub.com/FSM

[cbrooks0003]

Yup, that's where I got it! That manual has been a life saver more than once, and I'm greatful to whoever made it available here!

As far as the transmission goes, they aren't really that bad; just many many many parts. But if you follow the manual step by step, its pretty much all there. That's how I did the last one I rebuilt. This one is a lot more complicated than the 3 speed TH400 I did though Also, one of my friends is a transmission guru, and he gave me a few pointers and offered his help if I needed it. We'll see if I am still saying this after its back in the car, I guess

[3Q Jay]

you drilled out the vb spacer plate to increase flow to the high clutch and 2nd/4th gear band?
i do not reco using the really stiff spring in the kit for the 1-2 shift, the trans makes a nice firm 1-2 already.
change your rear main (engine) seal while you have it out and replace the tailshaft seal. if there is any doubt aobut your turbine sensor, do it now while it is so easy to get to.
make sure tq conv is fully seated in the pump before installation. i've rebuilt c-6's in my youth, once busted a pump gear by not properly seating the conv and then cranking down on thebellhousing to engine bolts......

[cbrooks0003]

Yes, I drilled out the spacer plate, and I was not going to use the spring in the kit. I still wanted it to drive like a luxury car and all I also got a new rear main ready to go in. I've also been there and done that on the converter not being seated... only for me it was on the th400 I did... I actually redid the whole thing because of all the pump gear pieces inside the transmission after that
The weird thing is, in the forward clutch there is a thicker steel that goes between the last friction plate and the thick retaining plate. It is 2.8mm rather than 2mm like the rest. My kit didn't include this, so I used the old one and my clearance is good. On the reverse drum, my clearance is about .065 where the max is .055. If I add an old plate between the last friction plate and retaining ring, like in the forward clutch, I get a good gap. The wave plate is in right, and the new drum matches the old, and the number of steels and friction is the same... and when I took the old one apart I had no burned clutches, but still a huge out of spec gap... and according to the manual, and the way it was before I took it apart, the last clutch plate rides against the retaining plate directly. There is no retaining plate available that is thick enough to get me into spec either... so I'm not sure what to do... leave the extra plate in, or keep the huge gap that seemed to work for 130000 miles before the low/reverse piston blew its seal...

Thanks for the advice!

[cbrooks0003]

Sorry, it was the high clutch with the extra steel before the retaining plate, not the forward clutch...

[cbrooks0003]

My bad again... I mixed up the reverse clutch and the high clutch frictions. The reverse clutch frictions are thicker and took up the gap. Now, in the forward clutch, spec for the frictions is .08 max, and my new ones are .079. But the old ones I took out are way under that, and are even made with thinner steel plates. I looked and there are no other sizes made for the forward clutch, except for the re4r01a, and they have the wrong number of teeth. So if I use the old retaining plate, I have no gap at all. I don't get it. I've checked and rechecked everything, so I guess I'm going to either get a thinner retaining plate, or if they have to order it, take it to my buddy's machine shop and have him mill about .010 off of it. Maybe the factory got a good deal on some frictions made with thinner steel bases or something...
The other thing is, the manual says that 6 of the reverse brake frictions should be waves, and 2 should be flat. Well, none of the ones I took out were waves, and none of my new ones wewre either. Looking at the parts catalog from Transtar, I don't even see wave frictions available. I didn't even know they made wave frictions for anything... what would be the point?

[OwnerCS]

You're going to be the RE4R03A rebuild expert. How would you like to do more rebuilds in the future?

[cbrooks0003]

Let's wait and see how this one works first I've got it all back together (no parts left over, even), and I'm going to try and get it in the car this week. I can see the reason that rebuit units are so high though. Just the stuff to do a standard rebuild was about $600, and you don't know what kind of mess someone is going to turn in for a core. A complete pump assembly is about $200, though I got away with just the cover for $105. Components for an old Chevy trans are about half of that. Plus, $130 for all the solenoids, which should always be replaced during a rebuild. But adding labor and a small markup on parts, and you are easily at the cost of a factory rebuilt unit, unless you get lucky and don't need any hard parts... my friend told me that my transmission would have been about $1600 buddy price, about $2000 normally. I don't think the factory remans are that much more

[elwesso]

yeah and the factory remans get a complete new valve body from japan, so they're really a bargain considering what you get...

[qship96]

yeah and the factory remans get a complete new valve body from japan, so they're really a bargain considering what you get...

Too bad they dont stand behind their rebuilds with a warranty longer than 12,000 miles- considering the price, it should come with at least a 4 year/50,000 mile warranty, if not longer.

[BadQ45t]

No kidding, however, you and I know if you get a high quality rebuild and you treat it with kid gloves from day one it SHOULD give you 150-200 of good service. But shelling out for one of those they should give you a like-factory new warranty. What do those run these days?

[TODD0341]

cbrooks,

How is this whole project moving along? Have you put the trans back in yet? Driven the car by chance??

[cbrooks0003]

I got everything done and put back together, and the car drives better than it ever did! Under normal acceleration, the shifts are as smooth as before, but under hard acceleration it no longer takes forever to shift into second. Its firm, but not harsh if you know what I mean. Also there used to be a slight vibration ever since I bought the car that has disappeared. Shortly after I finished it, a friend of mine at the local BMW dealer told me about a used 545I they had with low miles, so I ended up selling my Q for $4200 (almost what I paid for it 3 and a half years ago), and I bought the BMW. The Q drove better than new in my opinion, since I've heard they have always been known for that lazy 1-2 shift. Plus I have the Tokico Blue stuts on it. I think those two selling point let me get top dollar (around here anyway) for it. That and the low miles (130,000 on a 96... less than 10k a year) and the interior that looked like it had never been sat in....

[txQ45]

I started rebuilding the RE4R03a last year to support the 300Zx twinturbo for 700=rwhp...
Had to rebuild 6 of them before I got it down.. There's alot of things that have to be done to it before it's ready to go.
I was also the first person in the US that I know of or can find that had a REverse Manual Valve Body in this transmission and I ran that for over 6 months before I changed it back.
Built 2 for over 700 and 1 for 550 so far and have one running in my car..
I don't understand why someone would change to a manual from a auto when the auto is capable of doing everything and more that the manual does

[flyingbrick]

Would you be able to create a thread detailing what you recommend people do to make the transmissions last longer, handle more power, shift faster, ETC ETC ETC.

I've just recently had mine in pieces and its back together now (but not used it yet) however im all for making the shifts faster and harder and the DIY approach shown here.

I can't afford $1,000 NZD or so for an upgraded valve body :-( so any advice is much appreciated.

-Nathan

[maxnix]

yeah and the factory remans get a complete new valve body from japan, so they're really a bargain considering what you get...

Too bad they dont stand behind their rebuilds with a warranty longer than 12,000 miles- considering the price, it should come with at least a 4 year/50,000 mile warranty, if not longer.

No one does, except when new in a new car.

Dealer will also require radiator replacement.

[maxnix]

Would you be able to create a thread detailing what you recommend people do to make the transmissions last longer, handle more power, shift faster, ETC ETC ETC.

I've just recently had mine in pieces and its back together now (but not used it yet) however im all for making the shifts faster and harder and the DIY approach shown here.

I can't afford $1,000 NZD or so for an upgraded valve body :-( so any advice is much appreciated.

-Nathan

Q45tech already did on his second (new) transmission. Basically, BG flushes every 25K with M1 ATF and 6 oz. of Lubeguard Red. Sold it last 173K miles(shift times increased by .5 seconds) and it want on at least another 20K before he lost track of it.

You don't want "harder shifts" if you want longevity. The TCU retards timing during shifts in part for longevity.