700R4 hunting for gear over 50 mph - The 1947 - Present Chevrolet & GMC Truck Message Board Network

BB72CHEVKT · 07-10-2013, 11:33 AM

I have had this problem since I had the transmission rebuilt 6k miles ago but thought it was because I was running 2.8? rear end gears. I took the burb to a different shop and they confirmed I had 3.73 rear gears. I was thinking that once the gears were swapped to 3.73 the gearing would be right and solve the problem but apparently I had 3.73's the whole time. It does have a lock up kit installed. I am going to try to take it to the tranny shop next week but was wonding what you guys think.

Longhorn 70 · 07-10-2013, 11:42 AM

I would disconnect the lockup first. If that stops the "hunting" you may have adjustments you can make. It should just be one or two wires on the left side of the transmission.

**Ol Blue K20** · 07-10-2013, 12:03 PM

I hope it's not bad, have you called the tranny shop to see if they think it's an adjustment issue?

BB72CHEVKT · 07-10-2013, 12:19 PM

Quote:

Originally Posted by Ol Blue K20

I hope it's not bad, have you called the tranny shop to see if they think it's an adjustment issue?

I am going to take in in next week. The fluid is still pink as can be.

ZombieWeinerDog · 07-10-2013, 07:28 PM

what do you mean hunting for gears? my lockup senses vacuum and will sometimes switch in and out of lockup as engine rps decrease, then increase again.

YOUNG GUN C10 · 07-10-2013, 07:47 PM

idk about your transmission troubles but if it was hunting for another gear with the 2.8 rear gears.... switching to a 3.73 would be worse..... the numerically lower gears (2.8) are for a higher top speed, slower acceration............... while numerically higher gears (3.73) are for lower top speed, fast acceleration vehicles

YOUNG GUN C10 · 07-10-2013, 07:49 PM

do you mean hunting for gears as in trying to shift up or down shifting????

ezstriper · 07-11-2013, 08:00 AM

what lockup system are you using ? TV cable setup ?

**Ol Blue K20** · 07-11-2013, 10:55 AM

By hunting he means the trans can't make up it's mind 3rd 4th 3rd 4th etc......

Longhorn 70 · 07-11-2013, 11:02 AM

Is it hunting 3/4 or is it hunting lock/unlock?

**Ol Blue K20** · 07-11-2013, 11:19 AM

Quote:

Originally Posted by Longhorn 70

Is it hunting 3/4 or is it hunting lock/unlock?

HMMMMM.......that's a good question Longhorn. I didn't think of that, I guess that's why there's tranny guys..

Longhorn 70 · 07-11-2013, 11:34 AM

Yeah...Good transmission guys are a big asset.

If he disconnects the lockup wire on the transmission, he'll soon find out if it is 3/4 search or lock search for free.

BB72CHEVKT · 07-11-2013, 02:08 PM

I am running a Lokar kickdown and using Painless wiring for the lockup. It can decide if it wants to be in 3rd or 4th at times when over 50 mph. I am going to take it back to the shop.

ezstriper · 07-11-2013, 03:31 PM

thats either TV cable adjustment or issue inside trans...now you can have cable adjusted right at closed throttle and the ratio be off and cause issues...it is critical...

BustedCrank · 07-12-2013, 02:29 AM

More then likely its locking and unlocking. It was one of the main complaints for most people with these transmissions. The problem? Most people cant keep their foot steady when they drive, they drive on and off the pedal, constantly moving their foot. Not saying that is your issue, but a lot of people have that problem.

To check if its locking/unlocking or actually shifting is easy. When driving and you think it has unlocked(or downshifted) drop the shifter down to third gear. If it shift down, it was just unlocked. If it does nothing, it is shifting gears.

Probably just a tv cable adjustment is all that is needed. If you are using a factory style cable with the adjustment up by the carb. There is a "D" shaped looking button. Push it in and slide the cable so it is all the way tight, then move the throttle to wot and it should ratchet to where it needs to be. This isnt always perfect, but it usually makes a good starting point.

Longhorn 70 · 08-08-2013, 12:12 PM

Well??? Did the shop get that bad boy going?

BB72CHEVKT · 09-19-2013, 12:12 PM

Ok, finally got it into the shop. He fixed a small leak and the lock up. He said it was not drawing enough vacuum at idle and was turning itself off electically if I unerstood him correctly. He also fixed a leak.

67ChevyRedneck · 09-19-2013, 12:54 PM

So have you driven it yet?

BB72CHEVKT · 09-19-2013, 12:55 PM

Quote:

Originally Posted by 67ChevyRedneck

So have you driven it yet?

I have not picked it up yet. I will let you know once I have driven it.

07-10-2013, 11:33 AM	#1
BB72CHEVKT Junior Member Join Date: Mar 2007 Location: Hideaway, TX Posts: 4,950	700R4 hunting for gear over 50 mph I have had this problem since I had the transmission rebuilt 6k miles ago but thought it was because I was running 2.8? rear end gears. I took the burb to a different shop and they confirmed I had 3.73 rear gears. I was thinking that once the gears were swapped to 3.73 the gearing would be right and solve the problem but apparently I had 3.73's the whole time. It does have a lock up kit installed. I am going to try to take it to the tranny shop next week but was wonding what you guys think. __________________ 71 Suburban 350/700R4 Project Trixie 72 CHEVY,Highlander,SWB,396,T400

07-10-2013, 11:42 AM	#2
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Re: 700R4 hunting for gear over 50 mph I would disconnect the lockup first. If that stops the "hunting" you may have adjustments you can make. It should just be one or two wires on the left side of the transmission. __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

07-10-2013, 12:03 PM	#3
Ol Blue K20 Proprietor of Dale's Corner Join Date: Nov 2012 Location: Vacaville , CA Posts: 16,245	Re: 700R4 hunting for gear over 50 mph I hope it's not bad, have you called the tranny shop to see if they think it's an adjustment issue? __________________ "Some Days Chickens And Some Days Feathers" Dale XNGH ECV Sam Brannan 1004 R.I.P. 67ChevyRedneck R.I.P. Grumpy Old Man R.I.P. FleetsidePaul

07-10-2013, 07:28 PM	#5
ZombieWeinerDog Registered User Join Date: Oct 2008 Location: Sparta, MI Posts: 446	Re: 700R4 hunting for gear over 50 mph what do you mean hunting for gears? my lockup senses vacuum and will sometimes switch in and out of lockup as engine rps decrease, then increase again. __________________ 1972 longbed- 454 1967 shortbed- 355

07-10-2013, 07:47 PM	#6
YOUNG GUN C10 Registered User Join Date: Jul 2013 Location: Campton Kentucky Posts: 11	Re: 700R4 hunting for gear over 50 mph idk about your transmission troubles but if it was hunting for another gear with the 2.8 rear gears.... switching to a 3.73 would be worse..... the numerically lower gears (2.8) are for a higher top speed, slower acceration............... while numerically higher gears (3.73) are for lower top speed, fast acceleration vehicles

07-10-2013, 07:49 PM	#7
YOUNG GUN C10 Registered User Join Date: Jul 2013 Location: Campton Kentucky Posts: 11	Re: 700R4 hunting for gear over 50 mph do you mean hunting for gears as in trying to shift up or down shifting????

07-11-2013, 08:00 AM	#8
ezstriper Registered User Join Date: May 2013 Location: fredericksburg Posts: 26	Re: 700R4 hunting for gear over 50 mph what lockup system are you using ? TV cable setup ?

07-11-2013, 10:55 AM	#9
Ol Blue K20 Proprietor of Dale's Corner Join Date: Nov 2012 Location: Vacaville , CA Posts: 16,245	Re: 700R4 hunting for gear over 50 mph By hunting he means the trans can't make up it's mind 3rd 4th 3rd 4th etc...... __________________ "Some Days Chickens And Some Days Feathers" Dale XNGH ECV Sam Brannan 1004 R.I.P. 67ChevyRedneck R.I.P. Grumpy Old Man R.I.P. FleetsidePaul

07-11-2013, 11:02 AM	#10
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Re: 700R4 hunting for gear over 50 mph Is it hunting 3/4 or is it hunting lock/unlock? __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

07-11-2013, 11:34 AM	#12
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Re: 700R4 hunting for gear over 50 mph Yeah...Good transmission guys are a big asset. If he disconnects the lockup wire on the transmission, he'll soon find out if it is 3/4 search or lock search for free. __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

07-11-2013, 02:08 PM	#13
BB72CHEVKT Junior Member Join Date: Mar 2007 Location: Hideaway, TX Posts: 4,950	Re: 700R4 hunting for gear over 50 mph I am running a Lokar kickdown and using Painless wiring for the lockup. It can decide if it wants to be in 3rd or 4th at times when over 50 mph. I am going to take it back to the shop. __________________ 71 Suburban 350/700R4 Project Trixie 72 CHEVY,Highlander,SWB,396,T400

07-11-2013, 03:31 PM	#14
ezstriper Registered User Join Date: May 2013 Location: fredericksburg Posts: 26	Re: 700R4 hunting for gear over 50 mph thats either TV cable adjustment or issue inside trans...now you can have cable adjusted right at closed throttle and the ratio be off and cause issues...it is critical...

07-12-2013, 02:29 AM	#15
BustedCrank Registered User Join Date: Mar 2013 Location: In the rain Posts: 17	Re: 700R4 hunting for gear over 50 mph More then likely its locking and unlocking. It was one of the main complaints for most people with these transmissions. The problem? Most people cant keep their foot steady when they drive, they drive on and off the pedal, constantly moving their foot. Not saying that is your issue, but a lot of people have that problem. To check if its locking/unlocking or actually shifting is easy. When driving and you think it has unlocked(or downshifted) drop the shifter down to third gear. If it shift down, it was just unlocked. If it does nothing, it is shifting gears. Probably just a tv cable adjustment is all that is needed. If you are using a factory style cable with the adjustment up by the carb. There is a "D" shaped looking button. Push it in and slide the cable so it is all the way tight, then move the throttle to wot and it should ratchet to where it needs to be. This isnt always perfect, but it usually makes a good starting point.

08-08-2013, 12:12 PM	#16
Longhorn 70 Registered User Join Date: Dec 2012 Location: Chandler AZ Posts: 1,149	Re: 700R4 hunting for gear over 50 mph Well??? Did the shop get that bad boy going? __________________ 1970 Longhorn, Front Disc, 350/4 bolt, 882 heads, HEI, Edelbrock, 700R4, HO-52/4.11. 1996 Corvette, Collector Roadster, LT4, 396, 450RWHP, 6sp, 4.11/Dana44/posi 5 point roll bar And let us not grow weary of doing good, for in due season we will reap, if we do not give up. Gal 6:9

09-19-2013, 12:12 PM	#17
BB72CHEVKT Junior Member Join Date: Mar 2007 Location: Hideaway, TX Posts: 4,950	Re: 700R4 hunting for gear over 50 mph Ok, finally got it into the shop. He fixed a small leak and the lock up. He said it was not drawing enough vacuum at idle and was turning itself off electically if I unerstood him correctly. He also fixed a leak. __________________ 71 Suburban 350/700R4 Project Trixie 72 CHEVY,Highlander,SWB,396,T400



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09-19-2013, 12:54 PM	#18
67ChevyRedneck Hittin E-Z Street on Mud Tires Join Date: Nov 2004 Location: Greenville, SC Posts: 23,090	Re: 700R4 hunting for gear over 50 mph So have you driven it yet? __________________ Jesse James 1967 C10 SWB Stepside: 350/700R4/3.73 1965 Ford Mustang: 289/T5-5spd/3.25 Trac-Loc 1968 Pontiac Firebird: Project Fire Chicken! 2015 Silverado Double Cab 5.3L Z71 2001 Jeep Wrangler Sport 4.0L 5spd 2020 Chevrolet Equinox Premium 2.0L Turbo 2011 Mustang V6 ~ Wife's ride American Born, Country by the Grace of God 1967 CST Shop Truck Rebuild! My 1967 C-10 Build Thread My Vintage Air A/C Install Project "On a Dime" Trying my hand at Home Renovation! 1965 Mustang Modifications!

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