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-   -   700R4 Lockup question (https://67-72chevytrucks.com/vboard/showthread.php?t=18568)

69&72Bowties 07-16-2002 05:23 PM

700R4 Lockup question
 
How many of you guys running the 700r4 the kits that lockup your convertor in 4th only and manual lockup in 2nd and 3rd.

I want to wire mine where it will lockup in any gear and not just in 4th.. I dont want to put a switch on it... That looks and sounds gay!

Please give me your thoughts...

Longhorn Man 07-16-2002 05:29 PM

Why do you want it to lock up in all gears? It drops 70% of the fluid into the pan when it goes into lockup, and if you are still trying to get up to speed, it will put more of a taxing on your fluid. It also drops the torque multiplication and you lose rhe 'pep' going through the gears.

69&72Bowties 07-16-2002 05:30 PM

I really dont know.. I just have been reading that some people have it where it will lockup in 2nd or 3rd...

Espically 3rd when they are towing? Maybe I am wrong and should just get the kit from 700R4.com and not worry about any of it?

Low69CST 07-16-2002 05:36 PM

I don't think you want it locking in all the gears. Its considered a gas milage idea. I think if you do it the way your thinking you'll wear it out. The converter will be locking/unlocking constantly in city driving. Every single person I know that has done this retro has bought an adjustable mph switch so that converter locks up once the tranny shifts into over drive only. Plus, if you ever just nail the gas, i'm not sure how that torque converter will take all that abuse while trying to lock/unlock.

Low69CST 07-16-2002 05:40 PM

maybe if someone is going to tow a big trailer but want their RPM's up, they will have it so the converter locks up once they are cruizing down the highway. If this is what your after, the adjustable mph switch is exactly what you want. It will lock up the conveter at a certain mph no matter what gear your in. For instance, say your transmission always shifts into od no later than 50mph. So you set the switch to lock up at 55mph. No matter if you keep your selector in Drive instead of overdrive your converter will still lock up at 50mph in Drive. That way you can lock your converter and keep the rpm's up.

1-PU70 07-16-2002 05:42 PM

I have a 700R4 in my 70 and I have it to lockup in 4th only. I have the B&M lockup control that ties into the spedo cable. You set it to lockup at whatever speed you want. I have mine set at 65. It unlocks at 55. Set it once and your done. I am very happy wit it and would recomend it to anyone.

bigvinnie 07-16-2002 05:56 PM

I lock up in 4th only.... I tow in 4th/non-lockup with no problems. If your vacuum switch is set up properly, during towing you'll upshift to 3rd on a hill like you should, no worries...

And believe it or not, I have a hidden manual lockup switch, so you can't see if it's gay.... and it's one of those special silent switches, so it doesn't sound gay either...

now, lockup in 2nd..... that could qualify as being gay.

Get the 4th lockup kit, a vacuum switch and have someone who knows what they're doing set it up for you, and forget about it.

72chevyLWB 07-16-2002 06:48 PM

I have the painless wiring 700R4 lockup kit. It locks up in 3rd and 4th gear only. When you get on the throttle it unlocks and also when you hit the brakes

Longhorn Man 07-16-2002 06:52 PM

It's not really a good idea to tow in over drive, ask my dad, he discvered this when he had no forward gears anymore. (he didn't believe the first tranny guy, nor the second...after the 6th!!! call, he called me and told me i was right about this.)

Gordo 07-16-2002 08:30 PM

I stripped out the wiring, plugged the case with a freeze plug and ran a non-locking converter. I would have gained about a 200 rpm drop in OD at cruising speed if I had went with a lock-up but I prefered to keep it simple. This has served me for 40plus K including towing, so far with no complaints.

72chevyLWB 07-16-2002 08:36 PM

what size tires are you running? I have 27" tall tires with 3.73's and am running 3,500 RPM at 75 (maybe 80 if speedo is off). It bugs me, but it might be normal.

Longhorn Man 07-16-2002 08:53 PM

1 Attachment(s)
Gordo, the lock-up is most of the trouble when towing. If I ever get an overdrive, i will be doing the same as you have done. Did you use the 700's verter or one out of a th350/400?
and 3500 @ 75 seems kinda high to me, but I could be wrong. look at the tach and my acurate speedo. This is with a TH350,a nd a 3.07 gear in the rear with 27 - 28 inch tires. (the angle makes it look slower, I was closer to 95 really)

Gordo 07-16-2002 09:24 PM

My tires are also 27-28 high and my tach reads 1800 at 55, 2050 at 65 and 2350 at 75. My trans shop supplied the converter and I never did ask them about that, I will and let you know in the future which converter they sold me. Some say the trans runs hotter this way but with the extra cooler I've yet to see it run over 175 degrees pulling my drag box. Unless I'm luggin' the hills, I leave it in OD.

By the way longhornmail, doin 95 and takin pictures? Was that before or after a few cold ones? (LOL)

Longhorn Man 07-16-2002 10:34 PM

LOL, it was the morning comute.

69&72Bowties 07-17-2002 10:06 AM

I appreciate all of your help... I think I might go with the painless wiring 700R4 lockup kit.. It sounds simple and easy to install. I like the idea of locking up in 3rd and 4th only.. Sorry Bigvinnie, Didnt mean nothing by the gay switch thing... Hope I didnt offend you... I am just type of person that likes to keep things looking stock and not rigged like some people do... Nothing intended...

Appreciate all of your help...

Bryan

one legged lance 07-17-2002 07:33 PM

799r4.com was great to me
 
All I can say is that I got everything from Bowtie Overdrives and they helped me over the phone with the setup. Running since March and loving it. Including a couple of Phx to Tx towing trips that were smooth as silk. I have a 350 with 3.73 gears and 295/50-15.
Again the 700r4.com folks were very nice to deal with.
1 Leg Lance

69&72Bowties 07-18-2002 08:23 AM

Lance,

Does your convertor lockup in 3rd?

Bryan

red71cheyenne 07-18-2002 11:15 AM

The first time I put the tranny in, I ran the lockup through the brake switch so it was hot all the time until you stepped on the brake. After the tranny died!, I had the tranny guy put a block off plate in the TCC solenoid and now it only locks up in 4th at 40 mph. Seems to shift better than the original one and so far I've not had any problems with this one. Its only got about 500 miles on it so far. I don't think the original wiring had anything to do with the tranny failing, as the guy had to replace nearly every part in the tranny. I think it really just depends on how you want it to work. If you are concerned, talk to some tranny people you trust and if he will honor his work, go for it. Jeff.

Bamm 07-18-2002 12:35 PM

I use a TPI switch that is too easy to install and I haven't had a problem with it yet........JB

Bamm 07-18-2002 12:36 PM

I think it sells for around $75.00 but if you can catch them at a show you can get a better deal...........JB

crew70 07-18-2002 05:06 PM

when towing you do not want to have your converter locked up.... you want it pumping the oil through the cooler so you dont burn it up.instead of dumping it into the pan.

Low69CST 07-18-2002 05:19 PM

The fluid would have to continue to circulate when the converter locks up wouldn't it? Otherwise, why doesn't the tranny lock up like you shut the oil pump off in a motor?

crew70 07-18-2002 05:25 PM

the flow of oil is slowed when the converter locks up. thats why these tranis burn up when you are pulling something.the oilgets hot and will boil out the dipstick.

Longhorn Man 07-18-2002 07:00 PM

70% of the fluid is dropped into the pan. The tranny figures that since you are not accelerating, and there is no big load, (hill) that it does not need the extra pressure.
So it drops the 70% and runs on the remaining 30%.


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