4R70W shift kit or tuning?

[JoshT]

I guess this is kind of going to be a chicken or egg, which came first type of thread.

We just got done with the AWD V8 swap into my 99 Ranger last week. Got some bugs to work out, but so far I'm liking it. I can already see a few things that will have to change though.

1) Speed limiter has got to go. After running the truck on a "closed course" I realized that the speed limiter kicks in right at 90 MPH cutting either ignition or fuel. I won't often have need to go that speed, but I know in areas of the state the normal interstate traffic can exceed that. I want ability to keep up with, get away from, or get out of the way of the other traffic. As such, it telling me that I can't keep up won't cut it, especially not when it's still pulling strong right up to that limiter. Also I don't like nanny features telling me what I can't do.

2) Transmission shifting has got to get better, it's way too lazy.

3) Speed limiter has got to go. Did I mention that already?


The donor vehicle for this swap was a 2000 Explorer 5.0L AWD. EDIT: 180K miles on donor odometer. History unknown. Transmission still had dipstick knockout plug lying in the pan. Fluid was not burnt. Trans shifted fine for 100 mile drive home in donor with no signs of slippage. No signs of slipage in the 100-150 miles I've put on it since swap (and I've been heavy on the throttle), just lazy shifting.

I used ForScan to wipe all previously learned data in the PCM, when programming the PATS module after swap. Considering the stuff I fixed during the swap, I wanted a fresh start from the Explorer it was in. I know some vehicles in this era already did some learning and adjusting of shifting. Do these do that? Can I expect shifting to improve as I put miles on the truck? Not get great, but atleast improve or adapt to my driving style?

I will probably be getting a tuner for the truck to get rid of the speed limiter, I know that they can also tweak shift points and stuff for the transmission.

A shift kit would probably improve shifting a lot, but I just put the transmission in and filled it. I don;t really want to spend that kind of money on a relative unknown, atleast not before I've put several (maybe thousand) miles on it.

Regarding are transmission, are tuning and shift kit independent improvements, or do they need to be done as a pair.?Can I get improved shifting from a tuner now and install a shift kit later, or do I really need to install the shift kit first so that it can be accounted for in the tuning?

I would assume that the shift kit would probably have the bigger improvement, but I'd like to be a little more confident in the condition of the transmission before putting that money into it.

 

[vroomzoomboom]

you can firm up the shifts by increasing the line pressure with a hand held turner, but by only so much (and depending on what tuner you get, move the shift points as well). a shift kit will also make a major improvement without increasing line pressure.
i have had both. there are 2 different things you can do for a shift kit. buy a actual kit, or do what is called "the "J" mod" or "jerry mod". once again, i have had both lol. i had a transgo level 2 shift kit in one transmission. it was pretty firm, and would hit hard from first to second gear (would chirp the tires at wot), second to third was firm but not as violent.
the j mod, i found or at least for the trans that is was done for (in the truck now) is not as harsh, and if you can do it at home if you have the smarts to do it (and a trans is on my list of things i cant or trust myself to do).

J-Mod question, what does it do exactly - what are the...

www.tccoa.com

https://www.crownvic.net/tech/4R70Wnotes.pdf

 

[JoshT]

Thanks.

I haven't read through all that second link since I'm in my phone. It seems like there are different versions of the J-mod depending on year. The transmission I'm using us a 2000 model. I also have.

I also have a complete 1998 2wd Explorer 4R70W. I know that functionally they are the same, but I don't know how similar they are mechanically. Could I do the J-mod on the 98 valve body and swap it into the 2000 transmission?

My trans fluid is brand new. If I drain it into a clean container, I should be good to reuse it. I don't want to dump money into the transmission until I get some miles on it and know it's sound. The J-mod sounds essentially free though and if I can use the other valve body to modify it wouldn't have much down time either.

 

[JoshT]

@vroomzoomboom thanks for the links. They appear to be a good resources for performaing the J-mod, but I'm afraid that they and further research is leaving me more confused.

First off, I think I need to throw the notion of the J-mod being free, right out the window. Still cheaper than an off-the-shelf shift kit, probably better than those, and likely a welcome improvement over stock shifting. My fluid and filter both are brand new, so as long as I can catch it and keep it clean (I installed a pan drain plug) it should be good to reuse.

Year ranges and applications of valve bodies is throwing me off on doing the mod. Transmission in the truck is a 2000 Explorer AWD. I also have a 1998 Explorer 2wd transmission. Looking through the links, many say that it doesn;t apply to trucks. Would the Explorer 4R70W be considered a truck transmission, a car trasnsmission, or it's own thing. In the car transmissions it talks about pre or 98-up, obviously these fall in the latter year range, but are they the same as the car valve bodies.

I see information saying to swap valve bodies and to the J-mod on the new valve body, is that what I need to do. Is it as simple as installing a different VB? Would just installing a different valvebody make an improvement without the J-mod?

@CDW6212R is the only one I've seen clearly say that he has done the J-mod on an explorer transmission, but I haven't found the details of what he did yet.

What I've seen in the TCCoA forums, the work of this mod is definitely something within my capabilities. I am just having difficulty locating or determining exactly what version of the mod I need to go by, or if I would need to (or just should) buy a different VB to start with.

 

[CDW6212R]

The J'Mod is the main way to go for a 4R70W, given how long it's been around, and created by a Ford trans engineer. I haven't done the J'Mod, but I have done several other VB kits for the AOD, A4LD, and the 4R70W. I was doing those before the J'Mod came out, which was in the mid 90's I think.

The J'Mod should work in any 4R70W or AODE VB; the truck issue was a past thing with shift kits by various companies, they didn't all work in a truck VB, or for one case I found, a police CV AOD(those have a manual 2nd gear valve in them, instead of a manual 1st gear valve), a B&M shift kit was really harsh at light throttle in my 86 CV.

There are varying holes sizes you can drill for the J'Mod process, people on forums like the Thunderbird(TCCOA) debated what worked best for their cars. I made some notes ages ago, and later was told it isn't super critical that you match hole size of other people. I gather what's best is to replace the accumulators and their springs for the 1/2 and 2/3 shifting accumulators, make the J'Mod holes sized in the typical range listed in instructions, and do whatever VB upgrades you can from Sonnax kits.

The cost is minor for the new accumulators and springs, the reverse servo piston etc, and the J'Mod is your time. But the Sonnax parts are getting expensive now, about $100 last I looked. Plus Sonnax developed a new VB upgrade years ago which is not included in their big set of parts kit. It's about $75 and I think that's a really good thing to install, it varies the line pressure as the throttle is pressed harder. That means it doesn't make light throttle shifts harsh, but it adds more pressure as you get to WOT.

So I suggest the VB improvements, which can be done at any time at home etc, and finish with the PCM programming. The computer can alter the shifts and line pressure some, with a VB that's the best it can be and not leaking; the shifts should end up really nice(however you want them).

 

[JoshT]

I guess I read that wrong, or maybe you were just saying that you were considering and looking into it.

I haven't really looked into the Sonnax parts yet, but in past reading (may have been for 5R55E) I've seen the name crop up a lot. Which Sonnax piece is this:

Plus Sonnax developed a new VB upgrade years ago which is not included in their big set of parts kit. It's about $75 and I think that's a really good thing to install, it varies the line pressure as the throttle is pressed harder.

I'm guessing the line pressure booster kit (4R70W-LB1)?

And for the "big set of parts kit" you are referring to the Sure Cure Kit or the Zip Kit?

make the J'Mod holes sized in the typical range listed in instructions, and do whatever VB upgrades you can from Sonnax kits

Based on what I saw skimming through the j-mod instructions, I'd probably start out with minimum suggested drill size for all. See what improvement that gives before going larger. Can always take away more metal, but it's a little more difficult to put it back, especially on something like the seperator plate.

Sounds like I need to find a source that discusses both the J-mod and the Sonnax parts.

Also, would I be correct in thinking that my '98 2WD and '00 AWD valve bodies should be interchangable? That is assuming that both are actually the factory transmissions. If so it would make this process much easier as I could pull the '98 VB, do the J-mod and Sonnax upgrades on it, then swap it in.

 

[CDW6212R]

Yes, that Sonnax item 4R70W-LB1 is the one I meant is the newest upgrade and very desirable. That isn't in the Zip kit unfortunately, I'm not thrilled with the price of the LB1 kit either. That means that one thing in the Zip kit is not used if you buy that, they are for the same valve in the VB. I have both of them and plan to put those into my current 98 work truck when I retire and stop using it.

I'd use the VB which you think is the best, worked the best, lowest mileage, and didn't come from a trans with past issues. They are interchangeable but be sure the smallest "round" reinforcement plate is used with whichever you go with. Ford did away with that in the 2001ish range, which leaves a possible weakness(all fixed by adding the small plate, or the optional thicker VB plate).

You can make holes slightly smaller, using a steel ball and a hammer. I have done that for two holes way back in the AOD days, I slightly softened the 1/2 shift I think it was, using a TransGo HD kit. That was the best AOD kit ever, complicated but awesome driveability.

 

[JoshT]

Yes, that Sonnax item 4R70W-LB1 is the one I meant is the newest upgrade and very desirable. That isn't in the Zip kit unfortunately, I'm not thrilled with the price of the LB1 kit either. That means that one thing in the Zip kit is not used if you buy that, they are for the same valve in the VB. I have both of them and plan to put those into my current 98 work truck when I retire and stop using it.

I'd use the VB which you think is the best, worked the best, lowest mileage, and didn't come from a trans with past issues. They are interchangeable but be sure the smallest "round" reinforcement plate is used with whichever you go with. Ford did away with that in the 2001ish range, which leaves a possible weakness(all fixed by adding the small plate, or the optional thicker VB plate).

You can make holes slightly smaller, using a steel ball and a hammer. I have done that for two holes way back in the AOD days, I slightly softened the 1/2 shift I think it was, using a TransGo HD kit. That was the best AOD kit ever, complicated but awesome driveability.

Honestly, I'm not thrilled with the price of any of it, but it's going to have to shift better than it currently does. No slippage, just too lazy for lack of a better term.

Not really going to matter which I use then. I have no real history with either. Both transmissions were from V8 Explorers with around 180k miles. One was a '98 2WD the other a '00 AWD. I knew the previous owners of the '98 and they maintained it well, but when I got it had been rolled over and wasn't drivable. The '00 was a complete unknown, but it drove 100 miles home with no trans issues other than the same lazy shifting. Unregistered, uninsured, and lots of non-drivability related issues kept me from driving aggressive during that trip.

 

[CDW6212R]

Those both sound fine to use, the 180k is not great but that they had no known issues, that's the biggest plus. The 4R70W is very reliable, even with some common neglect. My last two 98 trucks have had the same typical mild shifting, that's normal.

If you upgrade the shift quality by making it firmer, that reduces clutch wear. If the VB has no future functioning issues, the trans can last a long time still. The wear of common parts is basically the clutches, solenoids, and accumulators(seals of them). The springs have been known to break with high miles, so replacing those is another wise move.

Doing the Sonnax VB upgrades greatly reduces potential future issues, which are the cause of 90% or more of all trans failures. That's why I keep suggesting those parts, those take care of most all needs, until the clutches(and etc) wear out. With top brand ATF, replacing the filter often enough, and full rebuilds should then be rare.