Why is my AOD shifting in to OD at Top End of track when in D?

[YELL03]

I have a H/C/I 1987 Mustang LX with a built AOD, TCI 3200 converter, and 4.10 rear.

1st time at the track with a bad rear I ran [email protected] on a 2.099 60', the 1/8th was [email protected].

Had the rear rebuilt and went back to the track last Saturday.
It came out a little better at 2.059 60', ran much better in the 1/8th at [email protected], but then came the problem.

It only ran [email protected] in the 1/4....
After that 1/8th it should have run at least 13.2@103
about the 1000 ft mark it shifted in to OD.
This happened whether I left it in D or did the AOD shuffle (1-D-1-D)
You can hear it on the video.

I am trying to figure out what is causing this.

1 - a bad TV cable or wrong pressure
2 - a bad shifter linkage, maybe D is still OD
3- a bad valvebody
4 - is the trans going bad (it was supposedly put in 4000 miles ago.

Here is the video:

https://www.youtube.com/watch?v=1PumnH499W0&index=1&list=UUBTQ6EbZgwPCIe1dppWe45w

 

[Mnstr50]

I was in the process of building an AOD for my fox, but aborted the idea when I figured out a properly built AOD (at least with the goodies i wanted) was going to result in a $4,000+ dollar bill. With that said, I communicated with Chris (Lentech) and he mentioned that in some occasions the AOD will shift into OD at the end of the track. However, his suggestion was going with a taller rear-end gear (like 3.55's), and a wide-ratio 4R70W gear set instead of the stand gear-set and 4.10's (which is the rear-end gear I also run).

Anyway, I would check the line pressure first, and then take a look at the valve-body. Obviously, you're running a shift kit with the standard 1-D-1 pattern.

I would reach out to Lentech, Silver fox, or PA further trouble shooting, and possibly swapping that valve-body.

Out of curiosity are you running a lock-up or non-lock-up torque converter? Also, with the stall speed and 4.10's, the 60-foot times are a bit soft, are you having traction issues?

 

[YELL03]

I was in the process of building an AOD for my fox, but aborted the idea when I figured out a properly built AOD (at least with the goodies i wanted) was going to result in a $4,000+ dollar bill. With that said, I communicated with Chris (Lentech) and he mentioned that in some occasions the AOD will shift into OD at the end of the track. However, his suggestion was going with a taller rear-end gear (like 3.55's), and a wide-ratio 4R70W gear set instead of the stand gear-set and 4.10's (which is the rear-end gear I also run).

Anyway, I would check the line pressure first, and then take a look at the valve-body. Obviously, you're running a shift kit with the standard 1-D-1 pattern.

I would reach out to Lentech, Silver fox, or PA further trouble shooting, and possibly swapping that valve-body.

Out of curiosity are you running a lock-up or non-lock-up torque converter? Also, with the stall speed and 4.10's, the 60-foot times are a bit soft, are you having traction issues?

My plan is exactly that, adjust TV pressure first and swap to a Lentech street terminator or Silverfox Valvebody second, one of the ones where you can shift 1-2-3 and toggle OD, but I don't want to do the VB if the trans is fried.

I bought the car from a guy and only know what he told me.
Supposedly the car had a TCI Street Fighter Converter which is a lock-up converter, it certainly feels like it locks up in 3rd and OD, I don't see the rpms jumping (slipping) on the highway.
Car seems to stall at 2800-3000 when brake torquing.
Definitely soft launches, I would figure even at 271rwhp STD (around 260=265rwhp SAE) it should easily cut 1.8 60's.
I have not had the car retuned, I found a dyno-sheet in the car after I bought it saying 271rwhp STD, but that was the baseline off spray when it was tuned for Nitrous.
I think ti made 413 rwhp on spray. I took the Nitrous out.
Supposedly the car has a 327 stroker at 10.8:1 compression with h/c/i, but runs soft for all that.

 

[Mnstr50]

My mild combo felt super soft with the bone-stock AOD as well. But I had it back on the rollers after I switched to a T5, and we actually pulled a lot of timing out of it, and gained substantial mid-range torque and bumped the HP on the top end.

With that said, it's always a mystery what was actually done to the trans. I purchased a donor car to do my v8 swap and the guy told me it had 3.73's, turns out it was the stock 2.73's (I didn't drive the donor car long enough to determine this when I first purchased it, it was just as close to stock as possible).

Anyway, The stock OD band is the main weak point, along with the lack of line pressure, but I'm sure you've done your research as well. When my tans went out, it was due to the 4.10's. The stock valve-body wasn't "calibrated" for the 4.10's and I burned up OD, then 3rd, until finally it just slipped in any gear with moderate throttle.

If you've got the funds to support a build, it's always the "easy/safe" option. Check the fluid and pan to see if you might have any metal in it. does the fluid smell burnt?

The premature shift into OD, and the way it's doing it still leads me to believe it's line pressure or VB related.

 

[YELL03]

My mild combo felt super soft with the bone-stock AOD as well. But I had it back on the rollers after I switched to a T5, and we actually pulled a lot of timing out of it, and gained substantial mid-range torque and bumped the HP on the top end.

With that said, it's always a mystery what was actually done to the trans. I purchased a donor car to do my v8 swap and the guy told me it had 3.73's, turns out it was the stock 2.73's (I didn't drive the donor car long enough to determine this when I first purchased it, it was just as close to stock as possible).

Anyway, The stock OD band is the main weak point, along with the lack of line pressure, but I'm sure you've done your research as well. When my tans went out, it was due to the 4.10's. The stock valve-body wasn't "calibrated" for the 4.10's and I burned up OD, then 3rd, until finally it just slipped in any gear with moderate throttle.

If you've got the funds to support a build, it's always the "easy/safe" option. Check the fluid and pan to see if you might have any metal in it. does the fluid smell burnt?

The premature shift into OD, and the way it's doing it still leads me to believe it's line pressure or VB related.

My 1st step is to have the TV cable adjusted or maybe replaced. It looks worn as you can see.
My 2nd step is to get a new valvebody preferable with a OD lockout via a switch like the Lentech Street Terminator I had in my old 92.
I don't want to wait and burn up my trans.

 

[YELL03]

I am seriously thinking of doing a new valvebody with constant line pressure.
Here is a pic from the track that day

 

[YELL03]

Tranny shop called me, the TV pressure was very very low.
He adjusted it and took it out for some runs, he says it now holds until 5500rpms in every gear.
He did say the shifts feel soft, he felt at this power it should easily break traction on each shift, but he said I should drive it and see what I think.
He said it is possible there is some tranny damage that was done, but again, he wants me to see how I like it before dropping big money on any work.
He also said the recently rebuilt rear is making some funky noises and that there is a weird sound coming from the right front wheel area.
I am picking it up on Friday, for $85 at least it is better than it was and the guy gave me some good info.
I am wondering if it has a stock valvebody?

 

[YELL03]

Got the car back today.
First thing I did was get it washed, it was covered with dust from being inside the shop, they kept it inside at all times.
Just by adjusting the pressure via the TV cable the tranny now downshifts at part and full throttle to a lower gear where & when it should.
On my first WOT run it shifted 1-2 at 5600 (shift light came on and it is set for 5600) and 2-3 at a very slightly lower rpm, maybe 5500, I was keeping my eyes on the road as there was more traffic than I would have liked.
On some other runs it shifted a little earlier, maybe 5500.
The car feels much better.
As for the converter, the owner of the shop said it was only stalling to 1800?
That explains the 2.0 60' times.
Looks like a 3000+rpm converter and a new valvebody are in my future, but I would like to see how it runs as is.

 

[DarkMach1]

Ride as it is until you can get a c4, 4r70w or manual.

 

[YELL03]

Ride as it is until you can get a c4, 4r70w or manual.

I'd love to do a swap to a manual, but it would be expensive.

 

[MustangerMike]

silverfox SPT-MAC-TB is my VB of choice for the AOD. 1, 2, 3 shift pattern with OD on a switch, constant pressure (suited to your combo), forward shift man/auto WITH transbrake!

my car started with a T5, i swapped to an AOD, then i did the epoxy mod to it, then swapped to a j/y 4R70W with transgo manual kit (went 6.50's), then a TKO600 and now a C4. the C4 is b y far the least expensive trans to keep/maintain in our cars. but i would like to eventually do an AOD with 4r internals, one piece shaft and the above VB.

 

[MustangerMike]

on the other hand, a dogring T56 with the new S1 inline shifter would be WOW!

 

[YELL03]

silverfox SPT-MAC-TB is my VB of choice for the AOD. 1, 2, 3 shift pattern with OD on a switch, constant pressure (suited to your combo), forward shift man/auto WITH transbrake!

my car started with a T5, i swapped to an AOD, then i did the epoxy mod to it, then swapped to a j/y 4R70W with transgo manual kit (went 6.50's), then a TKO600 and now a C4. the C4 is b y far the least expensive trans to keep/maintain in our cars. but i would like to eventually do an AOD with 4r internals, one piece shaft and the above VB.

I got mine back and it seems to be running fine.
I am sending it out next week after the snow melts to get insepected and a dyno-tune to make sure the engine is making optimum power.
After that I think I'll drive it as is until something else breaks.