727 transmission/kickdown question

[Troy]

I got a call out of the blue the other day from someone local that my dad gave my number to. I don't know the guy or the car so this is just what I was told...

Car is a 74 Cuda with a transplanted 400 and 727. It's pretty cobbled together from a previous owner who tried to save money everywhere (think duct tape and bailing wire). New owner has only driven the car about 50 miles. His wife drove it to work the other day and it only wants to shift to the next gear if you "wind it up". I asked about a kickdown and there doesn't appear to be one (another person he talked to also mentioned it). I know you can skate by for a bit without a kickdown if you take it easy but what are the symptoms when it has finally messed up the transmission? What is the typical "fix"? As usual, money is an issue but we're also running out of summer so it can be fixed over the winter.

Thanks,
Troy

[SRT-68]

The top, smaller lever on the trans can be tied forward with a piece of wire. The trans will "short shift" but will be much more drivable around town.

[flyinlow]

The top, smaller lever on the trans can be tied forward with a piece of wire. The trans will "short shift" but will be much more drivable around town.

You could do that and see if that helps. It would be like driving with the kickdown linkage off. I have done this in a bind ,keeping the engine at low power setting, and it did not appear to bother the trans. Sometimes with no throttle preasure you can get a rev up on the 2-3 shift.

I think in the long term the best advice is:  Kickdown linkage, don't leave home without it.   

[Paul G]

Before I bought my 72 I drove a Cuda with the trans lever "tied down" in a fixed position. Not really very streetable that way. I used the Bouchillon kickdown cable on my 72. It is pricey, not the solution if your on a shoe string budget. But it takes all the geometry out of the linkage, especially if you dont have any linkage to start with.

[Troy]

Trying to find the kickdown linkage so back to the original question: what happens to the trans and how bad can it be to fix? He won't be driving it again until the linkage is found but he doesn't want to take it out at the beginning of next season only to find the trans is fried.

Troy

[flyinlow]

I am not a transmission expert. From what I know the throttle pressure lever does two things. First, as you increase it by opening the throttle it takes the governor pressure longer to overcome the throttle position pressure making the transmission shift at a higher vehicle speed. The governor pressure goes up about 1 PSI per MPH. The more throttle pressure you have the higher speed you need to make the valve body valves make the 1-2 and 2-3 shifts. Second,it increases the apply pressure to the bands and clutches to prevent them from slipping at higher power levels.
If you drive the car with the throttle pressure wired at the  wide open throttle position , the trans would shift late staying in first gear to maybe 30-40 mph and second until 70-80 and then shift firmly. I don't think it would bother the trans as much as the engine. Driving with idle throttle position would cause low speed shifts which could be over ridden by manually shifting, but if you drove the car hard the trans. might slip, causing rapid wear
If you put the linkage back on and adjust it and the trans. works OK it is probably alright. If you pull the pan and there is a lot of clutch material in the bottom ,you might have damaged it. If just a small amount it is probably good to go.   

[SRT-68]

You don't tie it to the WOT position you tie it to the throttle closed position(forward).

[Troy]

Ok, so I got to talk to the guy again last night and got more details. He was in his garage so I was able to get a much clearer idea of what was going on. He had a "Mopar Guy" stop by earlier who told him he had a 904, the trans was trashed, and he could rebuild it for $275. I told him it would be near impossible to install a 904 behind a 400 and the kickdown issues would be the same. So, after a few minutes giving directions on the phone, it really is a 400 with a 727. Any way, after closer inspection, there's a Lokar kickdown cable installed - which seems totally out of place considering all the shortcuts taken on the car. I have no idea if it is adjusted correctly though so I recommended trying that first. There's a local transmission shop who worked on his truck that also gave him a reasonable quote so he's probably going to have them rebuild it before it gets too cold to drive (hopefully after he checks the linkage!). The transmission looks like it's never been touched so my thought is that it's better to have it gone through now rather than finding out it's junk at the beginning of next season. I'll be going over to see the car in person some time soon.

Troy

[gtx6970]

Rebuild it for $275,

wish him luck with that

[Troy]

Yeah, that was the guy who thought it was a 904. The other shop (the one he's taking it to) was around $600 I think. Of course, the trans on my truck was supposed to be about the same and it cost a lot more than that...

Troy

[John_Kunkel]

Any way, after closer inspection, there's a Lokar kickdown cable installed - which seems totally out of place considering all the shortcuts taken on the car. I have no idea if it is adjusted correctly though so I recommended trying that first.

The Lokar is perfectly at home on a car with other shortcuts. The late shifts are quite common to the Lokar when their cryptic instructions are followed.

Adjusting the Lokar so that the trans lever is full back at WOT will most often result in late/no light throttle upshifts. The only way to make the Lokar work is to match the total travel of the carb attach point to the trans lever attach point...this usually requires drilling a new hole in the trans lever closer to the pivot.

[Troy]

Good to know. Thanks!

Troy