I currently have a 06 Yukon XL RWD 5.3 vortec, she has 227k. I'm wanting to do a motor swap but I'm having trouble finding a solution, I know if I get a performance motor, the transmission won't be able to handle the torque (please correct me if I'm wrong). I know it can only handle 360ft lbs, I want to get more power and torque, what's the best way to do this? Upgrade transmission, rebuild transmission? Then with my current motor I don't know what model it is, weather it's the lm7 or whatever, I have vin Z but I can't find anything else out on it. Any help or thoughts to think about would be so appreciated
I need some insight on a motor swap
- Thread starter triker97
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all of the above all depends on how much money you want to spend. so the question is do you really want to drop $10k+ on the vehicle?
if so then yes the best option is to have the transmission rebuilt with upgrades.
then you most likely will want to "try out" this new found power, so add a upgraded rear end to that equasion because it will be the next thing to go. GM rear ends are weak. so is the 4l60
if so then yes the best option is to have the transmission rebuilt with upgrades.
then you most likely will want to "try out" this new found power, so add a upgraded rear end to that equasion because it will be the next thing to go. GM rear ends are weak. so is the 4l60
iamdub
Full Access Member
Your '06 VIN Z is the L59, which is the FlexFuel version of the LM7. Really, the only difference is the intake manifold, if not just the injectors (larger for the FF engines). So, you can use any Gen3 engine. If the one you find isn't a FF version, just swap your current intake manifold onto it. All plug-and-play. A bolt-in upgrade would be the LQ4 (6.0). Swap it in and load a 6.0 tune and you're done. The LQ9 (also 6.0) has a little more power and some mechanical upgrades, but higher compression and needs 91 octane. Of course, there are power mods you can do to increase the stock power levels with any engine.
Your L59 specs
LQ4 specs
LQ9 specs
The 4L60 should definitely be rebuilt or replaced, if even just for its age. It won't live for very long if you wanna have fun with the newfound power. Either rebuild it with upgraded parts or buy a built one. There are known weak links that are automatically upgraded in just about any rebuild then there are upgrades from those, added as needed/requested. It's better to overbuild it once than to underbuild then rebuild.
This is the motor I'm looking at, just for reference. If I choose this route, what would be the next thing to look at? And when you say upgraded rear end, are you talking about the rear suspension??
Sorry for all the questions but also, now I've heard the 4l60e are trash, would a rebuild kit be able to handle the power from the motor? Or should I do a tranny swap with something more reliable?
Last question, would anything need to be done to the rear axle? Will the change in power and torque be a problem for it? I know I'll spend a good bit of money either way
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the 4l60 can be upgraded to handle more power, as for the rear end you could add a eaton detroit tru-trac those are fairly indestructible
you wouldn't need to worry about pinion ratio unless you wanted to be able to do burnouts down the whole block, but changing the ratio affects top end and possibly mpg.
@swathdiver @randeez @iamdub
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Then.... upgrade brakes, suspension, shocks, ( and a decal on your rear bumper, " Support Your Local Police".
Contact "California Performance Transmissions" for rebuild advice. ( The legend builder, Art Carr )
( Huntington Beach, Calif)
( I worked for him for a while)
Contact "California Performance Transmissions" for rebuild advice. ( The legend builder, Art Carr )
( Huntington Beach, Calif)
( I worked for him for a while)
That is helpful, but I don't have flexfuel, so I am a little confused, would a lm7 work for a swap?
iamdub
Full Access Member
Not doubting you, but why would your Yukon with a "Z" engine not be a FF? If the 8th character of your VIN is "Z", you should have an RPO code (white sticker inside glovebox lid) that says "L59". For engine swap purposes, it's irrelevant if you never run Ethanol fuel, at least, nothing higher than E10. But, I had to mention it if you're looking at engine options. It'd be nice to have the FF intake manifold, or at least the injectors, since they can support more power, as with more cubes.
An LM7 would work fine. No power difference, though. As for the Summit one you linked to in your reply to Wes, I wouldn't go that route. It's not just about the numbers. Looking at the basic cam specs they listed, that engine could make those power figures, but they'd be all mid- to upper-end gains. Having a fullsize SUV, and the XL version at that, it'd be weaker accelerating from a stop and normal city cruising. It'd pull hard when flooring it to pass someone while already going highway speeds, though. But, how often are you high-speed racing your Yukon XL? You do a lot more accelerating from stops. Do any towing? You can do some things to help, such as a looser torque converter and lower rear end gearing. The engine already has 10:1 compression which helps power across the board. For about the same money, I'd get a rebuilt 6.0 with a well-designed cam. You can maintain and increase power across the whole RPM range and not sacrifice any in the usable/needed ranges. The key is to have the whole package work together- engine, cam, converter, trans and rear end gearing.
Also, I wouldn't call the 4L60 "trash". It does what it's designed to do just fine. Mine has just under 227K on it. The last 27K have been behind a ~400HP 5.3 including track time, lots of WOT, 2nd gear and 4,000 RPM throttle steers, 145+ MPH jaunts... It might be "trash" from a performance standpoint when compared to other options. But, it can be built to support pretty much anything one would reasonably do with a 3-ton land yacht.
What all do you wanna do with this rig? "More power"- sure. But are you looking for a particular number for the bragging rights? Do you wanna accelerate harder? Climb highway inclines more easily? Tow a trailer more easily? Race stock F-bodies? You can get more power to the wheels, which you'd feel, with just a good tune. Or do you wanna be able to roast the tires on a whim?
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vin z is flex, look at the inside of the gas tank cap flip cover, there is a white sticker stating it is flexfluel as well as the rpo code list in the glovebox as dub already mentioned
Great questions, ok so first this is my daily driver, so I don't wanna go too crazy with the power. What I want to do is be able to accelerate better, burn a little bit of rubber every now and then and have a decent amount of HP for this rig. I don't do any towing, but you never know I might need to one day. I'm sorry I don't have all my cards in order for all this, but thats why I posted here, thank yall
These are what I found, honestly I've only been putting 87 in the tank
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ya that just says not use to use additives with e85 (ethanol) because additives are made for gasoline
Tonyrodz
Resident Resident
Let me give you some advice--I learned this the hard way--as mentioned--if you upgrade the motor, it's a domino effect. You'll need to beef up or upgrade your transmission, then eventually the rearend. My 1st motor upgrade was going from a 4.8 to a cammed LQ4 6.0. I had maybe 230-240k miles on the stock drivetrain. I assumed the trans was either rebuilt or replaced before I got it. It ran great. Felt a little froggy one day next to an Acura. We raced--I beat him. I slowed down, and then as I accelerated it was like it was in neutral. Had the trans redone--forgot to mention I also have a Circle D 3k stall converter. So it was beefed up internally, corvette servo, better and more clutches, and whatever else the guy did. I also like to burn rubber. Makes no sense, but it's jyst fun. Few years I blew the rear. I just bought a junkyard rear, I didn't have it rebuilt. It was cheaper doing a swap. So, as I said, it's a domino effect. You're gonna play, so you'll eventually pay. Just be prepared.
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Leave it alone... and only use a BUILT transmission. A properly built transmission and torque converter are designed on weight, tire diameter, current horse power, rear end spline, etc..
IT WILL WAKE UP.....
Your desire for engine performance seems like a marine spec.
( Marine engines: Imagine you buy a truck, and leaving the sales lot, you ONLY DRIVE up hill - ONLY. Lots of torque plus RPM. ( no guarantees on fuel use ) But you will kill the U-joints & rear end. ( Don't forget to cap your coffee mug )
Save your budget..... When you want to haul ass...... rent a car.... return it over night.
IT WILL WAKE UP.....
Your desire for engine performance seems like a marine spec.
( Marine engines: Imagine you buy a truck, and leaving the sales lot, you ONLY DRIVE up hill - ONLY. Lots of torque plus RPM. ( no guarantees on fuel use ) But you will kill the U-joints & rear end. ( Don't forget to cap your coffee mug )
Save your budget..... When you want to haul ass...... rent a car.... return it over night.
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Ya but I don't see anything saying it's flexfuel. I might be over looking, or just don't know what to look for, I see the L59 on the glovebox sticker though
LOL, it say's right on the sticker e85 or gas, that's what flex fuel is, you can use both or one or the other
And my dumbass moment has arrived, hahaha, but like I said that's why I'm here, so I can get knowledge and not **** this truck up.
So would my best bet be a engine rebuild or remanufactured L59? until I can do the same to the tranny and rear end
I'm ready for it, my wallet is not though
my preference is a built crate motor, be it whatever model. but me and my wallet tend to disagree
Marky Dissod
Full Access Member
Then don't waste your money. If you must spend, do so wisely, get more bang for your buck.
Your SPID sticker says GU6.
Unfortunately, GU6 is 3.42, which sucks sweaty arse.
You could very easily upgrade that RWD axle from 3.42, to 4.10, AND add a torque sensing limited slip differential, for UNDER $1900.
(That $3800 engine - before installation - could be replicated or even improved upon, for $2850 installed, by a clever shopper with time on his side.)
Back to topic:
4.10 would actually be a good investment, as your metro / urban stop'n'go MpG would actually improve.
4.10 MIGHT cost 2 - 4 highway MpG, depending on how you drive it, but it might be worth the extra SMILES per gallon to you.
My Tahoe has GT4 - that's 3.73 - and I'm sorely dissatisfied; I want 4.10 myself, as soon as I can afford it.
If I had your XL, just before the pcm retune that you should also do, I'd've corrected GM's mistake of 3.42, and upgraded to 4.10.
