Is my transmission sitting too high?

[House Money]

I have my LS3-4L75E installed but not really satisfied with how it sits. At this point I'm looking at trimming the upper floor panels as well as the forward part of the frame where the parking brake handle would mount - on both sides just to be able to remove the pan for future maintenance. Before I do that I wanted to get some feedback. I assembled the trans mount and adapter using the supplied 1-1/4" spacers but those spacers could be shortened quite a bit if in fact the trans needs to be lower. At this point I can't get the trans tunnel to fit down to the floor and think that would also be solved if the trans were lower.
DSC_0608.JPGDSC_0609.JPG

[DamnYankee]

Yours does seem high but kind of tough to see, but do you have the rubber mount bolted to the transmission first?
I'm running a T-56 so not exactly the same as you.
Also, my trans mount bracket is mounted with the legs going up. The spacers are between the rubber mount and the bracket.

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[cob427sc]

Definitely way too high. Looks like you could flip the trans steel cross mount the other way or upside down from the way you have it. That would drop the transmission several inches and everything will still bolt up. I have a different transmission but that was how I installed it.

[DamnYankee]

Just took these pics with my truck on the lift. I ended up using 2 large nuts for the spacers.

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[House Money]

Thanks to both of you for responding. The provided mount is for a Ford transmissions and it will not bolt up to the GM trans. FFR provides the adapter plate and I have it assembled per their drawing they sent me. As for flipping the frame bracket, I can't really do that as the trans will not drop down as the pan is resting on the floor and that frame bracket - see # 2 picture in my post, if you enlarge it you can see where I traced a possible trim line. If I lower the trans during the install so it is below the floor there is simply no way to fit the trans mount/adapter assembly, no matter how that bracket is flipped.

i'm wondering if I should just order the Energy suspensions GM mount that should bolt directly to the trans and I could then ditch that adapter plate and the spacers, that should gain me about two inches.

Thanks, Gary

[House Money]

I went ahead and ordered the short version of the Energy suspension GM mount, # 3.1158R - the red one was cheaper than the black - go figure! Should be here sometime next week.

[House Money]

Well, I got the transmission in and I think it fits better. But now I have some new issues. So I ended up using the FFR supplied parts but shortened the spacers a lot - down to a little over 1/2" - the trans pan now fits just below the floor. DSC_0610.JPGDSC_0611.JPG.

So now I feel like it is too low, there is hardly any clearance for the driveshaft U-joint: DSC_0612.JPG

And that leads to the next problem, with the driveshaft resting on the floor panel, the shaft comes no where close to meeting up with the rearend: DSC_0613.JPG

What do I have wrong here??

Thanks, Gary

[Pat Landymore]

This is what I did with my Big Block/Powerglide installation. I’m not saying I did it the correct way, just this is just how I got into the end zone. Note in the 2nd photo an additional safety loop.

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[Pat Landymore]

It may be in part you currently have your ride height ‘too high’ in the back. That will make the issue you have worse.

I don’t care and will adjust my truck as needed to keep a taller height...I live in a city of approx 1.3 million people with almost 3rd world roads in some areas....

[House Money]

An update to yesterdays post: I trimmed a portion of the floor on the right side, that allowed me to raise the trans an inch or so, the pan is still below the floor level. That gained me much needed clearance between the u-joint and the floor. It also allowed the driveshaft to mate up to the rearend. However, I still have hardly any clearance where the driveshaft passes the floor near the rear of the cab, maybe a 64th of an inch.

That brings me to what Pat Landymore posted last night: I think the rear of the chassis is too high.

So what to do? I have the double adjustable Koni shocks, which I believe are longer than the single adjustable shocks. The manual states that the chassis has two sets of holes: the top are for the hot rod and the bottom are for the truck. I'm not sure that makes any sense as the rear of the truck chassis is nothing like the hot rod.

Should I use the upper holes for the rear shocks?

Thanks, Gary

[Pat Landymore]

I suggest trying it and see how level the truck looks.

Just move the shock bolts for now to do a visual, you can move the suspension arm and 3rd link bolts afterwards if you like the direction it’s going. Shouldn’t take a lot of time that way as a test, keeping in mind you’ll drop it down a bit more when you move the other attachment points.

My 2 cents...

[House Money]

I suggest trying it and see how level the truck looks.

Just move the shock bolts for now to do a visual, you can move the suspension arm and 3rd link bolts afterwards if you like the direction it’s going. Shouldn’t take a lot of time that way as a test, keeping in mind you’ll drop it down a bit more when you move the other attachment points.

My 2 cents...

Pat, do you think I would have to move the control arms to the upper holes, or just the shocks? I ask because in the front, with the upper and lower control arms in the lower holes the shocks are in the upper holes on the control arms, as instructed by FFR.

Gary

[Pat Landymore]

I’d say certainly to test the idea you only move the shocks...when I think more about you mentioning your shocks are a bit longer, that should be all you need to do IF the ride height and clearance are what you want.

Don’t forget that if you jack the rear of the truck up by the frame that the driveshaft may hit the floor again....I have personal experience with that...no damage done thankfully.

[House Money]

I’d say certainly to test the idea you only move the shocks...when I think more about you mentioning your shocks are a bit longer, that should be all you need to do IF the ride height and clearance are what you want.

Don’t forget that if you jack the rear of the truck up by the frame that the driveshaft may hit the floor again....I have personal experience with that...no damage done thankfully.

I'll remove the driveshaft to prevent any damage.

[Pat Landymore]

Howdy Gary!

Did you get time to move the rear shocks up?
How did it turn out?
A very curious mind would like to know...
LOL

[House Money]

Howdy Gary!

Did you get time to move the rear shocks up?
How did it turn out?
A very curious mind would like to know...
LOL

Hi Pat, yes I did move the rear shocks to the upper mounting holes all other rear suspension parts remained in the lower holes. I now have right about 1/2" clearance between the driveshaft and the floor. One problem though is that the upper adjuster on the shocks - rebound I think - is now no longer accessible as it is inside that channel. But I did confirm with FFR that the longer double adjustable shocks are to be installed in the upper holes.

[House Money]

I thought I would update this with a couple of pictures showing how I had to trim the floor on the right side to make the 4L75E trans fit, as mentioned I ended up using the FFR parts provided and flipped the trans mount bracket from how I originally had it installed. DSC_0621.JPG DSC_0622.JPG

And another shot showing the engine installed, all bolted in and some parts reinstalled once the lift plate was removed. DSC_0619.JPG