Trans cooler lines
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Joined: Nov 2006
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From: Texas
Trans cooler lines
Hey members,
I need to know which trans cooler line is the return line on a 90' Corvette coming out of the radiator, top or bottom.I dont have any fluid in the trans right now because I installed a Pete K. torque converter and I wanted to install a trans cooler before putting in any fluid.
I need to know which trans cooler line is the return line on a 90' Corvette coming out of the radiator, top or bottom.I dont have any fluid in the trans right now because I installed a Pete K. torque converter and I wanted to install a trans cooler before putting in any fluid.
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From: Northern California
The Bottom radiator line is the Return on my "91".
When I installed my TransCooler, I connected the Bottom radiator line to the transcooler and then out of the transcooler back to the transmission.
When I installed my TransCooler, I connected the Bottom radiator line to the transcooler and then out of the transcooler back to the transmission.
Drifting
Joined: Jun 2001
Posts: 1,625
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From: Zagreb, Croatia
700R4 / 4L60 / 4L60E / 4L65E Technical Description
The 700R4 can be identified by the oilpan having a rectangular shape being longer front-to-rear than side-to-side and held to the transmission by 16 bolts, 3 bolts front, 3 bolts rear, 5 bolts left side, and 5 bolts right side.
The tailshaft housing is held onto the main case by 4 bolts (the bolt spacing is similar to the THM350), and uses a square-cut o-ring seal, and not a gasket. The typical width of this transmission where it bolts to the engine is 20 inches (510 mm) overall. From the engine/trans mating surface to the crossmember mount bolt is 22-1/2 inches (570 mm), and engine/trans surface to output shaft housing mating surface is 23-3/8 inches (594 mm) overall, with the tailshaft housing typically measuring 7-5/8 inches (194 mm).
Transmission fluid cooler lines on the 700R4 the bottom fitting on the right side of the transmission is the "out" line to the cooler and the top fitting is for the return line from the cooler. These fittings are 1/4-inch pipe thread, and CAN include an adapter from the factory for threaded steel lines in a SAE size. 4L60Es manufactured after 1995 use the modern-day snap-in connections as opposed to threaded SAE fittings.
The original version of the transmission had a 27 spline input shaft which was a common failure point. In 1984, 700R4s designed for use behind Chevrolet small block V8s received a 30 spline input shaft which used a different torque converter than its 2.8 V6 and 2.2 L4 powerplants. Between 1984 - 1987, internal components, from the ring gear to the oil pump housing, were updated, ending with the auxiliary valve body (for 700s manufactured after October 1986).
In 1995 the 4L60E received a PWM-controlled lockup converter.
Around 1996, a bolt-on bellhousing was phased in (along with a six-bolt tailhousing) when the transmission was bolted behind an inline four cylinder or the Vortec engine family.
The gearing for the 700 is:
First - 3.059
Second - 1.625
Third - 1.000
Fourth - 0.696
Reverse - 2.294
(commonly rounded off to 3.06, 1.63, 1.00, 0.70, and 2.29).
The 700R4 can be identified by the oilpan having a rectangular shape being longer front-to-rear than side-to-side and held to the transmission by 16 bolts, 3 bolts front, 3 bolts rear, 5 bolts left side, and 5 bolts right side.
The tailshaft housing is held onto the main case by 4 bolts (the bolt spacing is similar to the THM350), and uses a square-cut o-ring seal, and not a gasket. The typical width of this transmission where it bolts to the engine is 20 inches (510 mm) overall. From the engine/trans mating surface to the crossmember mount bolt is 22-1/2 inches (570 mm), and engine/trans surface to output shaft housing mating surface is 23-3/8 inches (594 mm) overall, with the tailshaft housing typically measuring 7-5/8 inches (194 mm).
Transmission fluid cooler lines on the 700R4 the bottom fitting on the right side of the transmission is the "out" line to the cooler and the top fitting is for the return line from the cooler. These fittings are 1/4-inch pipe thread, and CAN include an adapter from the factory for threaded steel lines in a SAE size. 4L60Es manufactured after 1995 use the modern-day snap-in connections as opposed to threaded SAE fittings.
The original version of the transmission had a 27 spline input shaft which was a common failure point. In 1984, 700R4s designed for use behind Chevrolet small block V8s received a 30 spline input shaft which used a different torque converter than its 2.8 V6 and 2.2 L4 powerplants. Between 1984 - 1987, internal components, from the ring gear to the oil pump housing, were updated, ending with the auxiliary valve body (for 700s manufactured after October 1986).
In 1995 the 4L60E received a PWM-controlled lockup converter.
Around 1996, a bolt-on bellhousing was phased in (along with a six-bolt tailhousing) when the transmission was bolted behind an inline four cylinder or the Vortec engine family.
The gearing for the 700 is:
First - 3.059
Second - 1.625
Third - 1.000
Fourth - 0.696
Reverse - 2.294
(commonly rounded off to 3.06, 1.63, 1.00, 0.70, and 2.29).
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Joined: Jan 2004
Posts: 3,783
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From: Northern California
When I disconnect the Top transmission line on the radiator and start the engine, trans fluid pumps Out of the hard transmission line.
When the Bottom transmission line is disconnected, trans fluid comes Out of the radiator.
The information you Quoted for a Stock 700R4 configuration is correct, the drawing is Incorrect for the Stock transmission/radiator line connections.
When the Bottom transmission line is disconnected, trans fluid comes Out of the radiator.
The information you Quoted for a Stock 700R4 configuration is correct, the drawing is Incorrect for the Stock transmission/radiator line connections.
Last edited by GKK; Jul 13, 2008 at 11:31 PM.
Race Director
Joined: Jun 2004
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From: WI
Picture of the output flow from the bottom of the radiator to the trans cooler then attached and flowing back to the trans on the stock line.
With non stock lines you could hook it up different, like in the picture.
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From: Texas
Team Owner
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From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
This is my set-up
Drifting
Joined: Jun 2001
Posts: 1,625
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From: Zagreb, Croatia
That picture shows lines routing with aftermarket cooler (it came with cooler instructions).
Last edited by Sliding; Jul 14, 2008 at 11:01 AM.
