LQ1 Transmission Cooler Lines

[Galaxie500XL]

Not long after I bought my '95 LQ1 convertible, I had some transmission issues. One of the first things I did was add a "factory" transmission cooler from a 3.8 Buick to the stock location my Cutlass would have used IF GM had bothered to install a transmission cooler, like they did on the 91-93 cars.

 

Anyhow, since the lines I got with the cooler came from a Buick, I had to sort of creatively cut, and bend lines to get the cooler to work.

 

The cooler lines are weeping now, and pretty much I need to replace just about all of them. I was thinking that if I do what I'd like, I'd prefer replicating what GM did on the 91-93 LQ1 Cutlasses, and put it as it would have been stock.

 

What lines would I need to buy to completely replace the rigged-up stuff I have now, and would this be a problem? Since I've never seen a 91-93, I really don't know what the factory setup looked like, or if all the little nooks and crannies on the earlier cars for lines to pass through are still present on the later cars.

[wolfebrian2120]

I have a 95 monte with the LQ1. I had to replace the lines going to the cooler in the radiator a couple years ago, they were rotted right through. I just bought them straight from the dealer. I'm wondering why you wanted to add the cooler. Didn't the orignal lines go to the radiator to be cooled.

 

It was my understanding that the transmission cooler was part of the radiator, eliminating the need for an additional oil cooler. I would think that you would have the same radiator.

[Galaxie500XL]

When I first bought the car, I had temperature dependent problems with the TCC. Adding the cooler had two advantages, first, the transmission stayed at temperatures below where the problem occurred longer, allowing me to drive the car to and from work most days with TCC, and overdrive, improving fuel mileage. If TCC isn't working properly T460E's disable overdrive, making the car effectively a 3-speed auto without TCC...not good for mileage.

 

Ultimately, though, the TCC problem turned out to be a somewhat common problem with the TCC apply piston sticking in the bore at higher temperatures. Eventually, I had the transmission rebuilt to eliminate the problem.

 

Additionally, keeping transmission temperatures down promotes siginificantly longer life of the transmission. All 91-93 LQ1 W-bodies came standard with a transmission cooler, 94-up, GM eliminated the cooler.

 

Besides, my total cost in adding the cooler was only $35.00...there really weren't any downsides to adding the factory cooler to the car.

 

I have a 95 monte with the LQ1. I had to replace the lines going to the cooler in the radiator a couple years ago, they were rotted right through. I just bought them straight from the dealer. I'm wondering why you wanted to add the cooler. Didn't the orignal lines go to the radiator to be cooled.

 

It was my understanding that the transmission cooler was part of the radiator, eliminating the need for an additional oil cooler. I would think that you would have the same radiator.

[RobertISaar]

i know 91-93 had the (engine) oil cooler, but not trans cooler... that ran through the radiator though, so it doesn't sound like what you're looking for anyways.

[Galaxie500XL]

I was under the impression that 91-93 LQ1 cars got a transmission cooler...but you are right, I'm not looking to put the engine oil cooler on the car.

i know 91-93 had the (engine) oil cooler, but not trans cooler... that ran through the radiator though, so it doesn't sound like what you're looking for anyways.

[RobertISaar]

[94 olds vert]

Alrighty, 91-93 LQ1 cars did get and do have a factory trans cooler. You have a 3.8 trans cooler mounted in your engine bay is that in the same place the factory one would have gone on a 91-93 car? I'm assuming NO.

 

I also don't now if a 3.8 and 3.4 trans coolers are the same, but they function the same. Mounting could be tricky of its bigger and wont for into the factory location.

 

If I had a early 3.4 car I would get pictures of the trans cooler so you can see where it goes. Maybe some searching on the forums or someone else can get you a picture.

 

You should try to find 91-93 factory cooler lines that are prebent so you don't have to mess around with lines that need bending. RockAuto or a local parts store may have the correct cooler lines for a 91-93.

[55trucker]

Anyhow, since the lines I got with the cooler came from a Buick, I had to sort of creatively cut, and bend lines to get the cooler to work.

 

The cooler lines are weeping now, and pretty much I need to replace just about all of them. I was thinking that if I do what I'd like, I'd prefer replicating what GM did on the 91-93 LQ1 Cutlasses, and put it as it would have been stock

 

When you say the cooler lines are weeping, where are they weeping?

when you bent up new lines, did you flare the tubing ends that slide into any rubber hosing to prevent possible leaks & slipping off the hoses?

[Galaxie500XL]

Total of 4 lines, right? The 3.8 cooler is mounted to the exact spot an LQ1 cooler would fit...in fact, the bolt hole was already there and threaded for one side of the factory bracket in the upper radiator support, the other side went underneath the dogbone mounting bracket, and fit perfectly.

 

Alrighty, 91-93 LQ1 cars did get and do have a factory trans cooler. You have a 3.8 trans cooler mounted in your engine bay is that in the same place the factory one would have gone on a 91-93 car? I'm assuming NO.

 

I also don't now if a 3.8 and 3.4 trans coolers are the same, but they function the same. Mounting could be tricky of its bigger and wont for into the factory location.

 

If I had a early 3.4 car I would get pictures of the trans cooler so you can see where it goes. Maybe some searching on the forums or someone else can get you a picture.

 

You should try to find 91-93 factory cooler lines that are prebent so you don't have to mess around with lines that need bending. RockAuto or a local parts store may have the correct cooler lines for a 91-93.

[Galaxie500XL]

The rubber portion of the lines are seeping transmission fluid, especially around the crimps. The rubber has deteriorated.

 

When you say the cooler lines are weeping, where are they weeping?

when you bent up new lines, did you flare the tubing ends that slide into any rubber hosing to prevent possible leaks & slipping off the hoses?

[94 olds vert]

You are running 4 transmission cooler lines? Are you still running the lines into the radiator?

[Galaxie500XL]

Yes...there's a line running from the transmission to the radiator cooler (line 1), a line exiting the radiator, modified by me running to the cooler in front of the radiator (line 2), a line exiting the cooler in front of the radiator, (liine 3), and the original return line, modified by me, attaching to the line coming from cooler in front of the radiator to the transmission. (line 4).

 

So yes, the coolers are in series, going from the original one in the radiator, then going to the factory cooler mounted in front of the radiator, then returning to the transmission.

 

You are running 4 transmission cooler lines? Are you still running the lines into the radiator?

[Crazy K]

what dafuk Rob??? LOL

 

 

INFO!!!!!!!!

 

91-93 3.4 cars had transmission coolers. They were also on some 91-93 3.8 cars. They were optional on 3.1 cars, perhaps as a special package. I have confirmed their presence on 3.1 88 - 91 (88 and 91 documented, for sure) internationals for instance. There presence might be found on other high end 3.1 cars, but I have not yet observed this to be true. All 88-93 cars so equipped except the TGP use the same auxiliary transmission cooler.

 

94+ cars have the optional notches for a slightly different variation of the transmission cooler, one of the lower notches is shifted, but a dremel or snip could make a new notch in the core support if needed. There do exist 94+ transmission coolers. I have one that came from a 9C1 or 9C3, and in Dayton, I observed a 9C1 that had the same cooler. The coolers themselves are identical, except for the layout of one of the mounting arms. Three holes in the same location, one moved. The fluid lines of a 88-93 are different than those of a 94+ cooler. the lines are routed differently as the 94+ core supposrt is wider and more square, displacing them.

 

Most if not all 91-93 3.4 cars also had oil coolers, which are virtually identical to the ones used on TGPs, and appear as a giant adapter between the oil filter and the engine. The same internationals mentioned above had oil coolers, even with 3.1s. I see minor variations in the design of the oil coolers, but it may be more indicative of different manufacturers. They all have coolant passing though them, with the feed hose coming from the threaded block plug port at the lower front of engine, and the return shared with the return line from the heater core with a T fitting near the waterpump.

[Galaxie500XL]

K:

 

The cooler in my car came from a 3.8 Buick Regal. As you stated, 3 of the 4 "legs" bolted right up, I made a notch for leg #4, just as you described. The only other "mod" I had to do was to slightly bend the legs outward, to gain clearance between the cooler, and the "X" brace that's permanently welded on later model convertible cars in front of the radiator...earlier cars had a bolt-in brace, with slightly flattened spots to gain that clearance.

 

It wasn't fun taking the plenum box that sits in front of the radiator on Cutlasses apart, but I did, and the cooler sits in the factory location, in front of the radiator support and "X" brace, and inside the box. The plumbing inlet/outlets on the aux cooler point to the driver's side of the car.

 

What I'm wanting to do is to replicate the plumbing the earlier LQ1 cars had for the radiator cooler/aux cooler, and get rid of the cobbed up stuff I did to make everything work...but I'm uncertain what lines I'd need to order to accomplish that.

 

BUT, if as you say, the radiator support is different on '94+ cars, that sounds as if it's not really possible.

Edited May 17, 2013 by Galaxie500XL

[55trucker]

Finally got over to my storage where the car lives.....here's a few pics of how the cooler is OEM in place,

it's fastened at the top via the header panel, the lower you can see displayed, the cooler lines run out the side of the cooler DOWN and then along the bottom of the header panel, one to the far side of the rad to the rad's cooler tank.

 

 

 

 

 

[Galaxie500XL]

Those pics help a bunch...thanks so much for taking the time!