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I'm about to start on my CVT replacement/upgrade and figured I'd document the process in this thread. I'll layout my build plan which'll include a brand new CVT transmission replacement but also various bolt-on power mod upgrades. The list will change since I have to inspect the car. If items are worn, they'll get replaced at this point or just upgraded. This will also include a BOM for parts purchases and as many pics as possible. The CVT transmission teardown is going to direct me on where I "may" be upgrading the new CVT as there are several internal improvements to be made to increase the strength and reliability.
Goal:
Basic goal is to get the Juke AWD CVT to withstand more torque from the additional modifications I have planned. I'm realistic about the Juke CVT, it'll never be as reliable at torque levels that the 6spd RS cars are running, so the goals are going to be conservative. I could trade up to an RS 6spd, but I won't be doing that. I considered it but I'm already in another car payment and the time isn't right, plus I need an automatic for the daily. A stock CVT trans can hold 210 lb-ft @ wheels no problem for up to 75k miles and potentially longer if meticulously maintained and tuned correctly. Typically but not always a stock CVT will start slipping at the 245 lb-ft @ wheel level which isn't a good thing for CVT belt life. I suspect those with RS models may have higher torque slippage values due to differences in TCM tuning from the factory. The ECUTek flash tunes may also have some part to play but I can't verify that. Mine never slipped until the belt wear went critical due to mileage. The goal is a reliable 230- 245 lb-ft wheel torque level and it must hold trouble free for +50k miles. That is more than plenty for a daily driver.
I could pay Level10 to provide an upgraded CVT transmission, but that's not my plan. The (1) member (i.e. ARF) I know of who has completely upgraded the CVT seems to have found some reliability at elevated torque levels so it's possible. I'm going to attempt to tie-in as many of the CVT improvements as possible in a DIY project. ANY marginal improvement in reliability and torque capacity I'll take. I'll be utilizing as much of these "off-shelf" upgrades as possible. The valve-body may eventually get sent out for upgrade as well but I can always do that at a later date since it's a simple removal/install procedure on the car.
The Mamba 19T turbo, 2J Racing downpipe, High flow cat/Injen midpipe, 2J 255 LPH fuel pump, and an FMIC will get installed as well if I'm not pushed for time. There are so many parts getting removed for the CVT trans that the extra labor isn't much different. I'll also be replacing the upper & lower radiator support, & bumper crash beam due to light corrosion.
Backstory:
Back in March I started having drive-ability issues with my AWD CVT at 75k miles in terms of belt slippage and rpm hunting while driving. I had the basic bolt-on mods on my signature and was running these mods since about 2012. I'm not easy on my transmission but I also never launch it. After alot of diagnostic testing I ended up taking the risk and replacing just the CVT valve-body and switched to AMSOIL and this temporarily fixed most of these mechanical issues but a few remained. When I did it I almost knew right away I should have bought a new CVT for just another $1200 more, but it was done. Eventually the plan was to swap a new CVT anyway next year but this would buy me some time. Then at 80k miles I started getting bored at stock power levels and I decided the trans could take some upgrades, which probably wasn't the smartest idea. The additional torque going from a stock (the car was detuned at this point) 236 N-m to 320 N-m ended up being too much for my worn out transmission. It was running great for a couple days then it gave (1) massive slip during an awesome 3rd gear pull near 6000 rpms, at which point I decided to crank the boost back down. Well, 2 days later the CVT catastrophically failed while heading to work. There was no indication or slippage, just a roll into the throttle and then a "free" revving engine in all gears. I have had many transmission failures on modified cars and this is the nature of the beast. I kept my momentum up and maneuvered around a couple of cars and picked a nice spot to coast the Juke and it finally came to rest. I ended up calling a tow truck and had to make a quick decision on the side of the road to divert the tow truck to my house instead of the dealership. I had already priced out the CVT parts vs. Dealer installed and it was looking like $2500 vs. approx $4500. At my house the driver backed the flatbed up and perfectly rolled her into position neatly inside my (2) car garage. The Juke is now sitting about 20" up in the air on my QuickJack car lift with the front clip removed and the teardown process has begun.
Progress:
To start off, here is the Juke raised in the air 20" on the Quick Jack 7000SLX with wheel ramps as backup supports. The QuickJack is sitting on it's "safety-lockout bars" and not hydraulic pressure. The Lift is rated for 7,000 lbs so the 3,160 lb curb weight is hardly stressing the lift. The rating mostly pertains to the hydraulic unit as the frame itself can lift 21,000 lbs. Jack stands cannot be used as safety backups on this type of lift unless they are pre-loaded against the chassis, neither can crib blocks under the wheels. The risk of vehicle collapse is low but still there. I initially had 6" steel pedestal risers for the lift but it proved much too unstable to trust while wrenching on the car. I also had medium durometer "rubber" riser blocks but they were collapsing on the inside under the pressure load from the vehicle weight. I replaced them with solid pine wood 2"x4" to raise the high durometer "uni-body pinch-weld" polyurethane blocks enough to get correct vehicle & lift clearances. This solution is working great and the mounts are not flexing whatsoever. When the front wheels get removed the car will have wheels lying flat under the unibody to catch a potential collapse.
The other pics is my FMIC design with the Setrab CVT cooler/integrated fan. This'll go in place of the stock side mounted FMIC. I have the Nismo RS bumper grill insert illustrated to improve radiator cooling I'm going to lose with the FMIC. I may switch to the treadstone 22"x 6"x 3.5" core as an alternate as well to avoid having to cut/weld the Garrett core endtanks.
I've pulled the front clip and today I'm starting on the driveshaft/propeller shaft removal from the transfer case. I'll also be pulling the battery/intake/etc. to gain access to the (4) topside CVT bell housing bolts. The car has some corrosion so the "bottom-side" will be challenging. Next after that will be removing the right wheel, partial suspension, then drivers axle and transfer case.
Goal:
Basic goal is to get the Juke AWD CVT to withstand more torque from the additional modifications I have planned. I'm realistic about the Juke CVT, it'll never be as reliable at torque levels that the 6spd RS cars are running, so the goals are going to be conservative. I could trade up to an RS 6spd, but I won't be doing that. I considered it but I'm already in another car payment and the time isn't right, plus I need an automatic for the daily. A stock CVT trans can hold 210 lb-ft @ wheels no problem for up to 75k miles and potentially longer if meticulously maintained and tuned correctly. Typically but not always a stock CVT will start slipping at the 245 lb-ft @ wheel level which isn't a good thing for CVT belt life. I suspect those with RS models may have higher torque slippage values due to differences in TCM tuning from the factory. The ECUTek flash tunes may also have some part to play but I can't verify that. Mine never slipped until the belt wear went critical due to mileage. The goal is a reliable 230- 245 lb-ft wheel torque level and it must hold trouble free for +50k miles. That is more than plenty for a daily driver.
I could pay Level10 to provide an upgraded CVT transmission, but that's not my plan. The (1) member (i.e. ARF) I know of who has completely upgraded the CVT seems to have found some reliability at elevated torque levels so it's possible. I'm going to attempt to tie-in as many of the CVT improvements as possible in a DIY project. ANY marginal improvement in reliability and torque capacity I'll take. I'll be utilizing as much of these "off-shelf" upgrades as possible. The valve-body may eventually get sent out for upgrade as well but I can always do that at a later date since it's a simple removal/install procedure on the car.
The Mamba 19T turbo, 2J Racing downpipe, High flow cat/Injen midpipe, 2J 255 LPH fuel pump, and an FMIC will get installed as well if I'm not pushed for time. There are so many parts getting removed for the CVT trans that the extra labor isn't much different. I'll also be replacing the upper & lower radiator support, & bumper crash beam due to light corrosion.
Backstory:
Back in March I started having drive-ability issues with my AWD CVT at 75k miles in terms of belt slippage and rpm hunting while driving. I had the basic bolt-on mods on my signature and was running these mods since about 2012. I'm not easy on my transmission but I also never launch it. After alot of diagnostic testing I ended up taking the risk and replacing just the CVT valve-body and switched to AMSOIL and this temporarily fixed most of these mechanical issues but a few remained. When I did it I almost knew right away I should have bought a new CVT for just another $1200 more, but it was done. Eventually the plan was to swap a new CVT anyway next year but this would buy me some time. Then at 80k miles I started getting bored at stock power levels and I decided the trans could take some upgrades, which probably wasn't the smartest idea. The additional torque going from a stock (the car was detuned at this point) 236 N-m to 320 N-m ended up being too much for my worn out transmission. It was running great for a couple days then it gave (1) massive slip during an awesome 3rd gear pull near 6000 rpms, at which point I decided to crank the boost back down. Well, 2 days later the CVT catastrophically failed while heading to work. There was no indication or slippage, just a roll into the throttle and then a "free" revving engine in all gears. I have had many transmission failures on modified cars and this is the nature of the beast. I kept my momentum up and maneuvered around a couple of cars and picked a nice spot to coast the Juke and it finally came to rest. I ended up calling a tow truck and had to make a quick decision on the side of the road to divert the tow truck to my house instead of the dealership. I had already priced out the CVT parts vs. Dealer installed and it was looking like $2500 vs. approx $4500. At my house the driver backed the flatbed up and perfectly rolled her into position neatly inside my (2) car garage. The Juke is now sitting about 20" up in the air on my QuickJack car lift with the front clip removed and the teardown process has begun.
Progress:
To start off, here is the Juke raised in the air 20" on the Quick Jack 7000SLX with wheel ramps as backup supports. The QuickJack is sitting on it's "safety-lockout bars" and not hydraulic pressure. The Lift is rated for 7,000 lbs so the 3,160 lb curb weight is hardly stressing the lift. The rating mostly pertains to the hydraulic unit as the frame itself can lift 21,000 lbs. Jack stands cannot be used as safety backups on this type of lift unless they are pre-loaded against the chassis, neither can crib blocks under the wheels. The risk of vehicle collapse is low but still there. I initially had 6" steel pedestal risers for the lift but it proved much too unstable to trust while wrenching on the car. I also had medium durometer "rubber" riser blocks but they were collapsing on the inside under the pressure load from the vehicle weight. I replaced them with solid pine wood 2"x4" to raise the high durometer "uni-body pinch-weld" polyurethane blocks enough to get correct vehicle & lift clearances. This solution is working great and the mounts are not flexing whatsoever. When the front wheels get removed the car will have wheels lying flat under the unibody to catch a potential collapse.
The other pics is my FMIC design with the Setrab CVT cooler/integrated fan. This'll go in place of the stock side mounted FMIC. I have the Nismo RS bumper grill insert illustrated to improve radiator cooling I'm going to lose with the FMIC. I may switch to the treadstone 22"x 6"x 3.5" core as an alternate as well to avoid having to cut/weld the Garrett core endtanks.
I've pulled the front clip and today I'm starting on the driveshaft/propeller shaft removal from the transfer case. I'll also be pulling the battery/intake/etc. to gain access to the (4) topside CVT bell housing bolts. The car has some corrosion so the "bottom-side" will be challenging. Next after that will be removing the right wheel, partial suspension, then drivers axle and transfer case.



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