My LM7/4L60e Build (1 Viewer)

[reddingcruiser]

I have posted a lot of what's in here over the past 7 months in the popular "What have you done to your Land Cruiser this week" thread, but I thought it would be fun to put it all together with additional photos in one build thread with a little reasoning behind some of my choices.

I had contemplated this conversion for years but being a bit of an 'old school' guy I was happy with what I knew. Then an interesting proposition popped up, which was essentially a trade: my 5.7/700R4 for the 5.3/4L60e sitting on a pallet. Hmmmmmm, what do I do? Well, first I had to sweet talk the wife, then do a little research, tell myself it was going to cost more than I figured, take longer than it should and convince myself I was up to the challenge.

I know others before me have done this conversion, and while I like to see how those folks arrived at the finished product, no two rigs are ever going to end up the same. What would be the fun in that!

FJ40 purists close your ears. Having a Rubicon trip already under my belt I highly recommend this combination to anyone contemplating it. The 5.3L LS-series motors are smooth, responsive and have plenty of power. I was initially a little worried about going from 350 cu. in. to 327 cu. in., but that concern was totally warranted.

I made some choices along the way that may not have been the cheapest, but I wanted to be sure I had reliability. Braided hose and AN fittings was one of those choices. After having my share of hose failures over the years I decided that if I was doing this over a period of months I would bite the bullet and buy the hose and fittings a little at a time as the build progressed. I have no regrets.

Since I didn't start with the Toyota inline 6 and manual trans some things were already done after I installed my 5.7L/700R4 combo. This made the install a little easier but I had no idea how much I would be able to reuse and how much I would need to rework. The good news for anyone contemplating this conversion from an existing SBC conversion is the major mods are really concentrated on the transmission and transfer case mounts and reworking the drivelines. I had an early Downey adapter plate for my 700R4, so I when I used the AA adapter I had to build a completely new rear mount. If you have the AA adapter on a 5.7L/700R4 you'll probably have less to do, but more on that later.

And so it began:

 

[reddingcruiser]

The first order of work was mocking up the transmission and t-case for an trial fit in the frame. My earlier twin stick shifter bracket was not going to work since it was built around the Downey adapter. A little careful measuring and notes from the previous 700R4 install got the shifters to come out the same hole in the tans cover. The same with the Lokar shifter. The two-piece 4L60e case is a little different than the one piece case and the 700R4, and along with the AA adapter, some minor adjustments put everything back in the same trans cover hole. My only mistake, which I would discover later, was while the stock case is the same as the Orion in all respects to mounting surfaces and the location of the hi-lo shifter, the casting is MUCH beefier and caused a little heartache when I had to rework the rear mount. The empty OEM case was a lot easier to handle, oh well!

The transmission had been gone through before I got it but I gave it to my buddy, who owns a transmission shop. He upgraded the clutches and drums, added a shift kit and blessed it. It's such a pain to get any transmission out and back in I just didn't want risk having to deal with it.

At this point it was time to bolt everything together and get ready to slip it into the frame. But, a couple things needed to be resolved first. I wasn't completely sure how I was going to deal with the engine mounts. I had read other build threads where folks used the LS mounts, and the thought of chopping of my previous SBC mounts was not making me happy. Then, POOF! My new Summit Racing catalog arrived in the mail and right there in the LS series section was a set of mounts to convert the LS block to old school SBC mounts. A little online research lead me to LSX Innovations and a few bucks later my new mounts arrived in the mail, along with the adapter to allow me to hook up my mechanical oil pressure gauge.

 

[reddingcruiser]

The day came to set everything into the frame and I decided to do it without the t-case installed. Great choice, and after years of balancing my t-case on a floor jack came to install it, that nasty task came to an end with a quick trip to Harbor Freight to buy scissor-type trans jack - best $100 bucks I've spent in a long time.

The LSX mounts have 3 locations to position the SBC mounts and after a little measuring and pondering I used the far forward location for starters. The engine ended up too close to the firewall and after looking everything over I decided that was not going to work. The biggest issue was the rear driveline length - waaaay to short, like two universal joints and a slip yoke too short. Also, if you are contemplating this conversion, keep in mind my rear axle is already been moved back on flipped FJ60 springs and relocated mounts. An OEM FJ40 wheel base and suspension would be a bit trickier.

Because of the bolt locations where the LSX mounts attach to the engine block there is a significant distance between the forward and middle SBC mount locations. The middle location was the ticket. When I put my original radiator shroud and brackets in things really began to fall into place! The OEM fan ended up right in the middle of the shroud and right at the back edge, with plenty of space to keep the OEM fan clutch. The original steering shaft setup cleared, but just barely and would some rework down the road.

At this point the list of immediate things to resolve began to grow, the included:

1. Resolving air intake and air cleaner options
2. Where to pull vacuum for the brake booster
3. How to connect the cooling system
4. How to route the exhaust and the O2 sensors
5. How to cool the transmission

On that last item, I had previously placed my transmission cooler in front of the radiator since the radiator was not plumbed for it, but I had to sacrifice my 'Toyota' badge, and that was not going to happen this time. So, I began to look options.

You can see the LSX and AA SBC mount combo in the middle picture

 

[reddingcruiser]

Once the engine placement was resolved it was time to turn my attention to the rear mount. Up until now the transmission had been supported on a combination of jack stands and/or my floor jack, depending on what I was doing. The one thing I wanted to make sure of was the transfer case was high enough to maintain around 3º of rearward slope on the engine/trans and not require reworking my skid plate, even though I knew the t-case would be further back.

On the earlier incarnation of the SBC I had the typical 'propeller' mount on the rear of the t-case and I was determined not to go that route again for a number of reasons. First, it makes taking the t-case off for service a major pain in the rear. Second, it limits the flexibility of the frame by creating an very inflexible four point chunk of steel and aluminum in the middle of the frame. The single point mount at the rear of the transmission allows the frame to move a little more. (yes, I know the cross member is still attached to both frame rails, but the it can flex around the single point of attachment).

Since I already had two spare Energy Suspension GM mounts that was what I used, one for the install and one for a spare.

In order to avoid reworking the skid plate the new cross member would have to be higher. Once I made a template and attached it to the frame everything became fairly obvious. This is where some real fun began. First, the old cross member (that had already been moved back once) was not going back in. Then, the old scab plates would need to be removed from the frame. There's nothing more fun than laying under a rig scarfing off steel with almost nowhere to escape, worrying about what's catching fire while you are focusing on what you're doing. Bottom line, it all went well. Someday, during the next frame-off, I'll clean things up a little more, but's that's a ways off.

With a basic idea of what I wanted and a trip through my steel rack I decided what I would build. Being around structural steel most of my life I like the look of I-beam construction, and the thought of getting creative with some angles and a cut-out for the nose cone seemed like it had the cool factor.

And that's how I ended up with this:

Remember the earlier discussion about the 'mass' of the Orion, this is where the problems showed up. Once I had taken the OEM t-case off, stuck (or tried to) the Orion in place I ended up with some interference issues. With a little pruning I was able to save my work and still ended up with a nice rear mount. Distance to the ground from the bottom of the mount - 23 1/2", skid plate to ground - 22 3/4". Good enough for me.

 

[reddingcruiser]

The Devil is in the details. Up to this point the big items are in and things look like they are flying along, but this is where things actually slow to a crawl. Hundreds of little things to ponder, many affecting future choices. Geez, if I just left well enough alone.....

Well, I began on the inside of the tub so I could get the trans cover back on, heater in and put the fuel tank in, so I could work on the fuel system.

The red cable in the picture is my starter cable and follows the original path in my 5.7., then I realized in the pile of stuff I got I had the OEM 5.3L battery cable and starter cable setup, so this routing went away. Once the neutral safety switch was hooked up on the Lokar shifter the transmission cover went on.

On my 5.7 TBI I had problems over the years with external fuel pumps. A little reading and I learned the reason they are so much larger than in-tank pumps is because of heat. They need the larger mass to dissipate heat. So, several years ago I decided to put the fuel pump the fuel pump in the tank, just like factory-built TBI and fuel injected cars and trucks. This was made all the easier by talking to the winner of a brand new FJ40 tank at the 2014 Rubithon. Fortunately for me he owned a Toyota truck and only lived about an hour away, so when he called to make the deal I was up for a road trip. The nice thing about a new tank is you don't have to worry about blowing yourself up! And it opens options with heat and flames that would otherwise make even experienced folks uneasy. That said, the earlier version looked like this:

Knowing I needed a minimum of 58psi fuel pressure and after researching high pressure in-tank fuel pumps on the internet, with an emphasis on selecting something that would be on a parts shelf when I needed it down the road, I tripped across the 2003-04 Camaro/Firebird (edit: my bad - 2003 Chevy Tahoe, O'Rielly #MPA30028) fuel pump. After a trip down to O'Rielly's and measuring it against by existing (highly modified) TBI pump I found it was EXACTLY the correct length to sit on the bottom of the tank with just a little bit of spring pressure, as GM had intended. Even better, all I had to do was re-machine one of my original mating ring templates to accept the slightly larger diameter of the new pumps O ring (w/skirt) assembly. With a little grinding I was also able to use the OEM compression lock ring. Cool clips have since replaced the washers holding the ring down.

The only major modification to the pump itself was providing a place for the fuel filler overflow go. The fitting is captured internally with a nut but J B Weld was added for piece of mind. An added plus is the Camaro/Firebird pump has its own baffle, the fuel returns INTO the baffle and a one-way valve allows fuel to flow in, but not out, while in the tank. This means there is no need to find a way to keep fuel at the pump when the rig is off-camber. At the rate these engines use fuel, I would bet there is enough fuel for 15 minutes idle time in the baffle.

As you can see, once again, OEM GM connectors make change-outs easier, and I could live without the overflow connection until I get home if I had to. The GM to AN Fuel line adapters are one of my best 'finds', they make the transition to braided hose and AN fittings a plug-and-play job, and best of all you don't need the silly SST to remove the fitting, unlike the OEM connections! Using the fuel gauge rheostat on the new pump might possible with a little work on the FJ40 tank baffle, which might be an added plus when installing a Dakota Digital Dash.

 

[reddingcruiser]

Once I figured I could get fuel to the injectors it was time to move back under the hood, sorta. Since I had already installed braided line for the 5.7 TBI, the GM to AN adapters were used again to connect to the fuel rails. In the research I did it was apparent that an LS-series supply/return fuel rail with an integral fuel pressure regulator was the way to go. Fortunately, the deal came with an extra plenum and two fuel rails and a extra set of injectors Plus, this configuration fit into my existing fuel system. I did as much as I could to run the lines away from heat sources and in areas with good, ambient air flow. I've dealt with hot fuel issues over the years, and though TBI and fuel injected engines aren't inclined to vapor lock due to high fuel pressures, hot fuel is no bueno!

Bulkhead fittings get the lines through the tub between the seats. I've done my last rubber grommet/fuel line through the sheet metal install. Any time you need to make a sharp turn you either have to use a piece of bent steel/copper tube, a spring to avoid kinks, or live with a big radius of hose you try to keep out of harms way. Oh, and then there is those darn hose clamp connections.

One thing you may notice in the picture above is the OEM Toyota fuel supply/return lines stubbed off into a female/female AN coupling. Wanting to leverage my options while in the middle of nowhere, this allows me to use an aftermarket inline fuel pump (that came with the engine deal) with couple of AN to hose fitting I built, to get me out of a jam until a more suitable replacement arrives.

The other thing I had to turn my attention back to was the coolant system. In addition to the regular inlet/outlet issues, the LS-series engines have a 'steam line' to take high temp water and steam of the top of the block. Fortunately the LM7 only has two block connections to one outlet line. Ah, brings back memories of the old Chevy 400 cu.in. small block days, except this time GM got it right. The challenge became where to return the steam line. On the factory setup, GM returns it to a convoluted system that ends up in the recovery tank; and a trip to the GM dealer, a list of NLA parts and the space available under the hood of a 40 told me I would need to go a different route.

Enter the folks from Jags That Run! If you have never been to the JTR website, and you do conversions that involve GM engines and transmissions, you are missing an excellent resource. Among their list of goodies is a transition connector that goes from 1 5/16" (the size the hose from the water pump) to 1 9/16" (the size of my radiator inlet). It also has the 1/4" NPT connection for the steam hose and a petcock to bleed air from the coolant system.

You can see the steam connection and petcock in the picture. The extra length of tube I welded on to eliminate the need for a "universal" (which I hate) and make a clean transition to a simple 90º hose connection. A nice stainless coolant recovery tank finished of the system.

The outlet connection worked equally well, using a section of a commonly available OEM radiator hose (the Gates # is in the pic below)

Finishing up the coolant system, my existing heater hoses went right in to the LM7 water pump connections with the aid of a 5/8" to 3/4" reducer from NAPA, since the water pump connections are different sizes. And, remember my dislike for grommets through the tub? I finished up the install with bulkhead fittings and AN to 5/8" hose connections. The pic below shows the install in a early version. The shut-off valve replaces the OEM Toyota version originally on the firewall.

 

[reddingcruiser]

Back to making the engine 'go', I turned my attention to the throttle connection and miscellaneous vacuum and air connections.

I always say that sometimes it's better to be lucky than good, and I goy lucky on the throttle cable. When I did my 5.7 TBI install I had a complete donor vehicle to work with, so I took the GM throttle cable from the '91 Chevy PU and I also cut off the top of the gas pedal and grafted it to the Toyota pedal. As luck would have it, it came out the same place the original Toyota throttle pivot assembly did, giving me bolt locations on the firewall to work with. Then a trip the GM dealer yielded a throttle cable for an 2002-03 Chevy Silverado. Holding my breath I installed the new cable bracket, hooked the cable up to the throttle body, clipped to the top of the plenum, stuck the end through the fire wall and, Presto! It plugged right into my modified Toyota pedal, with the perfect amount of stroke. I added a small retaining clip using the existing bolt blind nut on the firewall to secure the cable.

The air intake system was pretty straight forward with the aftermarket parts available. I started with a Spectre kit for the 2004 5.3L Chevy Silverado, added a close-coupled 90º coming out of the throttle body, and did a lot of trial and error fitting, ending up with the filter pretty much a straight 90º from the throttle body. When you are doing the air intake install, you have to keep in mind that there is a limitation to the length of the wires to the MAF sensor. And if you want the engine to run right, you need it.

I used a custom-built harness from Howell EFI and also had them reprogram the PCM. I had them eliminate everything from the PCM except for the information and inputs necessary to run the engine and transmission. If you don't do this you will be forever getting codes from the computer for things that no longer exist in the system like the rear O2 sensors, door and window alarms, lights, and on and on. While you can just ignore the codes, the one you'll be looking for will need to be weeded from the rest of the garbage when you are trying to troubleshoot a problem.

The harness is truly plug and play. I had Howell provide a longer 'trunk' line so I could keep my PCM out of harms way, in my center console. I also had them stub out the wires for all the OEM digital gauge functions for use down the road.

Everything connected without a problem, except I had the wrong oil pressure sending unit. Even though I have a mechanical gauge, I wanted the PCM to know whether or not the engine had oil pressure. A trip to the auto parts store produced the correct sender.

Summit Racing provided the OEM GM PCM bracket (how's that for a pile of acronyms) at half the price the dealer wanted. The harness goes out the bottom, through the floor and up to the engine. Everything else in the picture is my stereo and ARB wiring.

 

[reddingcruiser]

The one thing you absolutely cannot use from the LM7 is the stock engine oil pan. It is waaaay to deep and the lower portion of the pan and the oil level sensor on the passenger side are going to want to occupy the same space as the front drive shaft someday.

There are several ways to fix this: you can invest $$$$$ in the Camaro/Firebird oil pan, or you can begin chopping on the stock pan. Having access to a TIG welder made option 2 more practical. The OEM LM7 holds 6 quarts, however, the Camaro/Firebird pan is 5 quarts. Chopping about an 1 1/2 off the bottom makes it a 5 quart pan. How did I determine where to cut the pan? Easy, I put 1 quart of water in the pan, measured down from the flange and transferred that to the outside. I also eliminated the sensor and tapered the side for a little more driveline clearance.

The pickup tube needs to be shortened, too. I did this before I welded the new bottom on by installing the tube in the engine, installing the pan AND gasket (otherwise you'll lose a 1/8"), and put a straight edge across to determine the correct amount to remove from the pick-up tube. The pickup screen needs to be about 1/4" off the bottom, and at the same slope as the bottom of the pan. If you have access to a TIG welder, use it. Otherwise, be very careful you don't leave a piece of wire or slag in the tube, you will not like the result when it gets into the lubrication system. Because you are taking the quart of oil volume from the bottom of the pan, the dip stick still reads correctly when full. I reinstalled the splash tray and added put everything back together. I added a new drain plug to the left side (OEM is at the rear) using a modified aluminum pipe coupler (cheaper than a bung) and welded up the sensor hole.

Here are pictures of the completed pan, with my forward skid plate installed.

 

[reddingcruiser]

The one thing I like about the 4L60e AA adapter to the Toyota t-case is the longer length. This allows you to use the full-size Toyota u-joint and slip yoke, but not without a little pruning on the oil pan.

During my first attempt I was under the impression that the splash guard for the dip stick was a critical piece and I made provisions for it to stay. In doing so I didn't completely eliminate the interference with the front drive shaft and more surgery was required. Thank goodness I have another pan to work with! Even with the clearance provided I still had a little rubbing after the last Rubicon trip. To solve the problem I have ordered a long spline slip yoke assembly from Marlin Crawler. This should completely fix the problem.

The rear drive shaft, though short, is a double cardin and works fine.

Other issues that required tweaking included the steering shaft. An additional u-joint and support bearing fixed the clearance issues at the headers.

Otherwise, everything fit cleanly between the engine, P/S pump and frame

 

[reddingcruiser]

With everything installed and a Rubicon trip under the belt, here are a few pictures of the completed product. On the passenger side you can see my solution to 2 problems. The transmission oil cooler ended up on the p/s fender and the temp never got over 160º on the trail. It's not on a thermostatic control yet, but that's coming. The other item is a 'box' to keep crap from being thrown onto the filter from the fan. The one you see is a steel prototype thrown on in anticipation of high water (that never materialized) and an all-aluminum one is in the works. The red 'battery' boxes and brackets on the d/s are OEM items from the 2002 - 2004 Chevy pickups and worked perfectly as a way to access by battery if I need to jump start the rig since my battery is in a tray and cover under the driver's seat. It also made a clean connection for my winch and the OEM starter cable which goes under the front of the engine and to the starter. Again an OEM GM choice to make replacement easier down the road.

The Toyota charcoal canister found a new home and was routed to the port provided on the side of the throttle body.

It's hard to see, but the air cleaner and MAF are supported by a bracket that comes off the cylinder head and is attached with the same band clamps that connect this assembly to the silicone coupler and tube.

The radiator in these pictures is not the same one in most of the previous posts. Just 5 days before I was planning to leave for the Rubicon, the original radiator sprang a leak in the top 4 fins next to the tank, both sides. What are the odds? I couldn't see the leak, nothing hit the ground, but the coolant always dropped to the same level. Pulling the shroud made the leak obvious. Aluminum radiators are generally a throw-away item when they spring a leak in the tubes or tank connections, but I was able to get a replacement in two days. The time wasn't wasted, I decided to replace the fan clutch since I didn't know the history of the original one.

You can just see the upper radiator hose from the water pump, this is the OEM 2002-2004 Chevy Silverado hose cut to fit my application. You can also see the coolant recovery tank mentioned in an earlier post.

Overall I am extremely happy with the result and highly recommend it to anyone sitting on the fence.

 

[deliverance]

Pic and final length of rear driveshaft?

 

[gator25]

@reddingcruiser how far over to the d/s is the engine sitting?

 

[White Stripe]

How much different does it drive compared to the 5.7?

 

[Ketzer]

I got overly excited when I read this as a LMM build... (Duramax designation...) Still, very cool!! Thanks for all the tips!!

 

[reddingcruiser]

Pic and final length of rear driveshaft?

It was tough to get a good angle, but you get the general idea. Angle is not bad at all. Driveline length will grow when the 4-link suspension goes in this winter

 

[reddingcruiser]

@reddingcruiser how far over to the d/s is the engine sitting?

Just about an 1 1/2" towards the driver's side. The LS-series engines are wider than the old SBC, but much of that is near the top of the engine. Basically, the centerline of the engine, transmission and t-case are where they were before. Though they had to be moved forward a bit because of the transmission length and AA adapter, side-to-side the shifters are dead center in their original locations.

 

[reddingcruiser]

How much different does it drive compared to the 5.7?

Ah, my favorite part! The only real similarity to the 5.7 is 8 cylinders, after that everything is much nicer.

It fires at the touch of the key. My 5.7 on it's best day never did that.

It is smooth, not just at idle, but throughout acceleration. Throttle response is excellent. However, some folks say that there is a difference when you romp on it (a lag) because the transmission downshifts electronically rather that with a TV cable. Me, I don't expect to romp on it in the rocks.

Fuel economy is waaaaay different than the 5.7. If you compare the stock OEM specs, you are basically getting more H.P. and torque from fewer cubic inches while using less gas, what a deal! When you are off-road fuel economy is a plus.

It's quieter! It took me a while to figure out why. It's because, even with the OEM air cleaner and filter on the 5.7, you're not hearing the TBI (a modified carb) sucking in air and fuel. In the 5.3, the plenum, direct fuel injection and air intake system don't produce the same sound.
Seriously, the first time I took it down the street I thought I was in a completely different vehicle.

Then there IS the cool factor.

 

[Ketzer]

It was tough to get a good angle, but you get the general idea. Angle is not bad at all. Driveline length will grow when the 4-link suspension goes in this winter

View attachment 1505843

What type of torque arm is this I see above the driveshaft?

 

[reddingcruiser]

What type of torque arm is this I see above the driveshaft?

It's a track/traction bar. My design with RuffStuff parts. It's been modified over the years as things changed under my 40.

 

[gator25]

Very nice, even with all you have stuffed in there its very clean and uncluttered. Looks to be a helluva machine.