r155 transmission a new solution to r154
01-20-16, 07:45 PM
#46
I think the general idea is that the case doesn't have adequate venting from gear windage or something along those lines on the R154. Any idea if this was improved or resolved?
I'm doubting too many 2wd 4cyl tacoma are pushing a whole ton of power through the gearboxes but would love to be proven wrong. A quick google search doesn't yield much info on on the rear seals of the R155 boxes.
I'm doubting too many 2wd 4cyl tacoma are pushing a whole ton of power through the gearboxes but would love to be proven wrong. A quick google search doesn't yield much info on on the rear seals of the R155 boxes.
01-20-16, 07:57 PM
#48
Whelp, some possible bad news.
According to rockauto, the Supra R154 uses a replacement rear seal made by NATIONAL #710689
and the 2006 Tacoma with R155 uses?
NATIONAL #710689
Theres a distinct possibility this darn seal will still blow out even on the newer R155 when pushed closer to the limit.
The W58 is a slightly different seal than the R154. Yes they can be interchanged but the W58 seal is tighter on a R154
According to rockauto, the Supra R154 uses a replacement rear seal made by NATIONAL #710689
and the 2006 Tacoma with R155 uses?
NATIONAL #710689
Theres a distinct possibility this darn seal will still blow out even on the newer R155 when pushed closer to the limit.
The W58 is a slightly different seal than the R154. Yes they can be interchanged but the W58 seal is tighter on a R154
01-20-16, 08:03 PM
#49
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As far venting goes you can always add a vent there is no discrepancy there.
as far as power and tq theres no reason for it not to handle as much or more than a 154 if should out perform it.
The martial used In the R family never changed it could only get better, this could very well be the end to extra cost of a 154 an out dated trans the if the gear ratios are an issue then you may swap the gears out accordingly...why not do second gear launch. Not to mention that these transmission were designed to haul extra load dont we all know that the tacomas are all work horses. there is no need for custom clutch custom drive shafts custom pilot bearing extension housing custom brackets. you all the parts at no extra cost
as far as power and tq theres no reason for it not to handle as much or more than a 154 if should out perform it.
The martial used In the R family never changed it could only get better, this could very well be the end to extra cost of a 154 an out dated trans the if the gear ratios are an issue then you may swap the gears out accordingly...why not do second gear launch. Not to mention that these transmission were designed to haul extra load dont we all know that the tacomas are all work horses. there is no need for custom clutch custom drive shafts custom pilot bearing extension housing custom brackets. you all the parts at no extra cost
01-20-16, 08:05 PM
#50
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Whelp, some possible bad news.
According to rockauto, the Supra R154 uses a replacement rear seal made by NATIONAL #710689
and the 2006 Tacoma with R155 uses?
NATIONAL #710689
Theres a distinct possibility this darn seal will still blow out even on the newer R155 when pushed closer to the limit.
The W58 is a slightly different seal than the R154. Yes they can be interchanged but the W58 seal is tighter on a R154
According to rockauto, the Supra R154 uses a replacement rear seal made by NATIONAL #710689
and the 2006 Tacoma with R155 uses?
NATIONAL #710689
Theres a distinct possibility this darn seal will still blow out even on the newer R155 when pushed closer to the limit.
The W58 is a slightly different seal than the R154. Yes they can be interchanged but the W58 seal is tighter on a R154
01-20-16, 09:11 PM
#51
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I think the general idea is that the case doesn't have adequate venting from gear windage or something along those lines on the R154. Any idea if this was improved or resolved?
I'm doubting too many 2wd 4cyl tacoma are pushing a whole ton of power through the gearboxes but would love to be proven wrong. A quick google search doesn't yield much info on on the rear seals of the R155 boxes.
I'm doubting too many 2wd 4cyl tacoma are pushing a whole ton of power through the gearboxes but would love to be proven wrong. A quick google search doesn't yield much info on on the rear seals of the R155 boxes.
01-21-16, 12:30 AM
#52
As far venting goes you can always add a vent there is no discrepancy there.
as far as power and tq theres no reason for it not to handle as much or more than a 154 if should out perform it.
The material used In the R family never changed it could only get better, this could very well be the end to extra cost of a 154 an out dated trans the if the gear ratios are an issue then you may swap the gears out accordingly...why not do second gear launch. Not to mention that these transmission were designed to haul extra load dont we all know that the tacomas are all work horses. there is no need for custom clutch custom drive shafts custom pilot bearing extension housing custom brackets. you all the parts at no extra cost
as far as power and tq theres no reason for it not to handle as much or more than a 154 if should out perform it.
The material used In the R family never changed it could only get better, this could very well be the end to extra cost of a 154 an out dated trans the if the gear ratios are an issue then you may swap the gears out accordingly...why not do second gear launch. Not to mention that these transmission were designed to haul extra load dont we all know that the tacomas are all work horses. there is no need for custom clutch custom drive shafts custom pilot bearing extension housing custom brackets. you all the parts at no extra cost
Why would Toyota go out of their way to redesign even tougher gears for an already very tough workhorse 2WD/4WD transmission architecture capable of overkill reliability in 300hp+ sports coupes and sedans just to have even more overkill reliability than that for 159hp and 259hp non-performance (and non-turbo) engines in their light duty trucks? The required strength for 259hp routed through a 4WD transaxle was already there to begin with.
I totally see this as Toyota adapting the same tough transmission design for several different applications from 4WD hauling to 2WD high horsepower turbocharged racing engines using a lot of the same R&D. The fact that we can adapt the R155 to do the work of the R154 even with a few differences is a great option. They can obviously take a lot of beating just like every other R-series transmission. All positives in my opinion
But stronger than the R154 which has already been proven up to 750whp MAX? The only way an R155 will reliably get beyond a similar power threshold is with a $5,000 PGS gearset swap... just as any R154 would require to do the same.
Last edited by KahnBB6; 01-21-16 at 12:37 AM.
01-21-16, 09:19 AM
#53
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Hang on a second. It's very likely that, if adapted and upgraded internally the R155 is probably just as strong as the R154 for power holding unless the gears aren't made of similarly strong alloy. I'd be surprised if they aren't made of the same metallurgy honestly. However... claiming that the light duty truck R155 is STRONGER than an R154 which was built for racing in high horsepower applications... I don't think that's the case.
Why would Toyota go out of their way to redesign even tougher gears for an already very tough workhorse 2WD/4WD transmission architecture capable of overkill reliability in 300hp+ sports coupes and sedans just to have even more overkill reliability than that for 159hp and 259hp non-performance (and non-turbo) engines in their light duty trucks? The required strength for 259hp routed through a 4WD transaxle was already there to begin with.
I totally see this as Toyota adapting the same tough transmission design for several different applications from 4WD hauling to 2WD high horsepower turbocharged racing engines using a lot of the same R&D. The fact that we can adapt the R155 to do the work of the R154 even with a few differences is a great option. They can obviously take a lot of beating just like every other R-series transmission. All positives in my opinion
But stronger than the R154 which has already been proven up to 750whp MAX? The only way an R155 will reliably get beyond a similar power threshold is with a $5,000 PGS gearset swap... just as any R154 would require to do the same.
Why would Toyota go out of their way to redesign even tougher gears for an already very tough workhorse 2WD/4WD transmission architecture capable of overkill reliability in 300hp+ sports coupes and sedans just to have even more overkill reliability than that for 159hp and 259hp non-performance (and non-turbo) engines in their light duty trucks? The required strength for 259hp routed through a 4WD transaxle was already there to begin with.
I totally see this as Toyota adapting the same tough transmission design for several different applications from 4WD hauling to 2WD high horsepower turbocharged racing engines using a lot of the same R&D. The fact that we can adapt the R155 to do the work of the R154 even with a few differences is a great option. They can obviously take a lot of beating just like every other R-series transmission. All positives in my opinion
But stronger than the R154 which has already been proven up to 750whp MAX? The only way an R155 will reliably get beyond a similar power threshold is with a $5,000 PGS gearset swap... just as any R154 would require to do the same.
01-21-16, 10:02 AM
#54
No offense man but your shooting down everyone's suggestions and research and just making assumptions now. You CANNOT say it will hold more power than the R154 when it's not even in your car yet, let alone not pushing over 700+ HP without blowing fluid out of the shifter or seals.
I know your new to this forum so no harm done and I commend what you're doing but some of us have years of hands on experience with these transmissions. Understand that you aren't the sole person who knows everything about a subject. You didn't invent this swap. Let's discuss and help each other, otherwise your going to find it very hard to ask for help later if you've always just told people they don't know what they're talking about.
01-21-16, 12:34 PM
#55
Ahhhhh utilizing the old tailshaft. Gotcha. This limits the use of going R155 for me. I already have an R154 and the only real problem I have with it is that rear seal. If this fixes nothing, I don't know how much utility this trans would have for me. Especially if the gears are physically the same width with the same theoretical strength.
01-21-16, 12:54 PM
#56
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Your not making any sense, were agreeing that it bolts up, there's no question there. In that same sense of being SOOO similar to the R154 means its likely going to have the same problems and capabilities.
No offense man but your shooting down everyone's suggestions and research and just making assumptions now. You CANNOT say it will hold more power than the R154 when it's not even in your car yet, let alone not pushing over 700+ HP without blowing fluid out of the shifter or seals.
I know your new to this forum so no harm done and I commend what you're doing but some of us have years of hands on experience with these transmissions. Understand that you aren't the sole person who knows everything about a subject. You didn't invent this swap. Let's discuss and help each other, otherwise your going to find it very hard to ask for help later if you've always just told people they don't know what they're talking about.
No offense man but your shooting down everyone's suggestions and research and just making assumptions now. You CANNOT say it will hold more power than the R154 when it's not even in your car yet, let alone not pushing over 700+ HP without blowing fluid out of the shifter or seals.
I know your new to this forum so no harm done and I commend what you're doing but some of us have years of hands on experience with these transmissions. Understand that you aren't the sole person who knows everything about a subject. You didn't invent this swap. Let's discuss and help each other, otherwise your going to find it very hard to ask for help later if you've always just told people they don't know what they're talking about.
And third you marked your self by saying r154s blow oil left and right I can post a list of a lot of guy running a r154 with way over 700whp with out oil Issues you seem to be having from your bad experience sorry man but you haven't even went into a r155 or have mentioned it in the past or idea from any of your posting here on clublex and never did I once post something about whp rating for the r155 I just stated the gear set looks like a r154 but a Lil beefer from my looking and there is no 1st gear thrust washer problem in r155 and you can use billet forks for strength so for you to say I invented something is so stupid on your part because you didn't put time into it and I did all I wanted was positive feedback and to show people research you are making it look like you have did this swap and had bad experience and the trans failed on you on your so called 700whp mark lol
01-21-16, 01:45 PM
#57
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Ahhhhh utilizing the old tailshaft. Gotcha. This limits the use of going R155 for me. I already have an R154 and the only real problem I have with it is that rear seal. If this fixes nothing, I don't know how much utility this trans would have for me. Especially if the gears are physically the same width with the same theoretical strength.
https://youtu.be/tWm5mY8t0IM
1036whp on a stock r154 trans takes it up to 8k rpm car weight is 3310lbs and he has had the car in the hi 9s
01-21-16, 01:47 PM
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Your not making any sense, were agreeing that it bolts up, there's no question there. In that same sense of being SOOO similar to the R154 means its likely going to have the same problems and capabilities.
No offense man but your shooting down everyone's suggestions and research and just making assumptions now. You CANNOT say it will hold more power than the R154 when it's not even in your car yet, let alone not pushing over 700+ HP without blowing fluid out of the shifter or seals.
I know your new to this forum so no harm done and I commend what you're doing but some of us have years of hands on experience with these transmissions. Understand that you aren't the sole person who knows everything about a subject. You didn't invent this swap. Let's discuss and help each other, otherwise your going to find it very hard to ask for help later if you've always just told people they don't know what they're talking about.
No offense man but your shooting down everyone's suggestions and research and just making assumptions now. You CANNOT say it will hold more power than the R154 when it's not even in your car yet, let alone not pushing over 700+ HP without blowing fluid out of the shifter or seals.
I know your new to this forum so no harm done and I commend what you're doing but some of us have years of hands on experience with these transmissions. Understand that you aren't the sole person who knows everything about a subject. You didn't invent this swap. Let's discuss and help each other, otherwise your going to find it very hard to ask for help later if you've always just told people they don't know what they're talking about.
https://youtu.be/zUpDcDfoQLQ
01-21-16, 03:51 PM
#59
supragt35, I think you in a rear seal problem denial. there are people who push the r154 past 700whp, yes we know that. no one is saying they break at 700hp, but most of them start leaking at that power. Some people deal with the leak and don't tell anyone. Its not like you want to leak all over a dyno or a drag strip anyways, its embarrassing and even worse dangerous.
I have read over and over again on peoples builds that have had the rear seal leak over 600hp. I personally have friends that have had them leak also over and over again, seal after seal, even using the w58 seal which is slightly tighter, guess what it does? it still leaks... and its not a good place to leak from when you are pushing that kind of power, cause the rear wheels are not that from from an oil leak if you follow.
Like I was going to do r154, then when I read about the ar5 I was excited to do that swap, then I learnt about the rear seal and I gave up on all the R series and W series transmissions. One of the reasons the getrag is so great is cause it doesn't have that issue at all. If I am upgrading the trans I will be choosing one that won't leak, or if not upgrading well then I wont run that much power.
One member put a sponge in the shifter housing and that supposedly helped, but not sure it solved it at all. Tons of members on here that you are talking to already have an r154 that is leaking or they are worried about it leaking, and they were trying to help tell you that before it leaks on you. no ones telling you not to try it out go for it I personally dont care how much hp it holds if it leaks every time you boost it hard, which is why I am going with the bmw 6 speed zf swap.
The one thing working in your favor though is the shifter housing from the soarer you are using, has an extra breather already installed on it, so that may help with the venting situation, or it might not do enough, hard to say but it should help out some but I am a bit skeptical.
I have read over and over again on peoples builds that have had the rear seal leak over 600hp. I personally have friends that have had them leak also over and over again, seal after seal, even using the w58 seal which is slightly tighter, guess what it does? it still leaks... and its not a good place to leak from when you are pushing that kind of power, cause the rear wheels are not that from from an oil leak if you follow.
Like I was going to do r154, then when I read about the ar5 I was excited to do that swap, then I learnt about the rear seal and I gave up on all the R series and W series transmissions. One of the reasons the getrag is so great is cause it doesn't have that issue at all. If I am upgrading the trans I will be choosing one that won't leak, or if not upgrading well then I wont run that much power.
One member put a sponge in the shifter housing and that supposedly helped, but not sure it solved it at all. Tons of members on here that you are talking to already have an r154 that is leaking or they are worried about it leaking, and they were trying to help tell you that before it leaks on you. no ones telling you not to try it out go for it I personally dont care how much hp it holds if it leaks every time you boost it hard, which is why I am going with the bmw 6 speed zf swap.
The one thing working in your favor though is the shifter housing from the soarer you are using, has an extra breather already installed on it, so that may help with the venting situation, or it might not do enough, hard to say but it should help out some but I am a bit skeptical.
Last edited by Ali SC3; 01-21-16 at 03:56 PM.
01-21-16, 04:11 PM
#60
CAN an R154 handle well over 750whp (WITH the known seal issues)? Yes... it technically can as we've seen demonstrated.
....For how long? (And "who cares, look at the video evidence" isn't a valid answer).
Edit: I'm seconding Ali SC3's concerns about severe leaking with that kind of power.
Every transmission has a duty cycle built into the design. High performance or truck transmissions and many Toyota manuals in particular have a lot of duty cycle built into them. Overkill for their stock applications in fact. Part of this is that Toyota wanted to go racing and part of it is their reputation for reliability. R-series gearboxes might be older technology but they tend to be very overbuilt.
Are those cars always tuned to 1,000+ whp with no low boost settings? And how are they shifted? 3rd gear tends to be the weak point in R154's at those VERY high power levels (again... highly expensive PGS gearsets are the only answer to that.. or a V160). Then there's the 1st gear thrust washer, front bearing retainer plate and not-overbuilt shift forks. Are you absolutely certain that the owners of both those cars didn't upgrade their R154's just to protect their investments? They sure did spend a lot of time perfecting the 7M's weaknesses. I'd find it hard to believe if they hadn't. That... or they have a spare R154 set aside in case it's needed. You can push 1000whp through them, sure. But the PROVEN safe long term limits for an R154 that's had internal strengthening is about 750whp. I'll be generous and say I've also seen 800-850whp quoted somewhere also. I prefer to go with the more conservative quote I've seen far more often.
Can you? Yes! And if you're lucky the R154 won't break. If you are so lucky, will your gearbox last nearly forever under those power levels like a V160 or Tremec TR6060? That has yet to be proven and so far the evidence says otherwise.
Is structural reliability up to 750-850whp not an impressive figure already for a transmission designed in 1986?
Look... this thread is turning into an argument rather than a healthy discussion about how to best adapt the R155. I have yet to see it proven that the gears are stronger (or weaker) than those in an R154 and I've not yet seen it proven that the weaknesses in all other R-series designs aren't inherent in this one. The less than ideal 1st-to-2nd gear spacing is something I'd like to see in practice.
^^ Still... those quibbles aside are minor to me considering what every other R-series is capable of well below 750whp.
supragt35, please, let's keep the discussion focused on the project you've taken on. I am interested to see where it goes. Even with the less than ideal gear spacing from 1st to 2nd I think it very well might be another option for SC owners if it doesn't require that much more modification than an MKIII R154 to bolt into our cars.
....For how long? (And "who cares, look at the video evidence" isn't a valid answer).
Edit: I'm seconding Ali SC3's concerns about severe leaking with that kind of power.
Every transmission has a duty cycle built into the design. High performance or truck transmissions and many Toyota manuals in particular have a lot of duty cycle built into them. Overkill for their stock applications in fact. Part of this is that Toyota wanted to go racing and part of it is their reputation for reliability. R-series gearboxes might be older technology but they tend to be very overbuilt.
Are those cars always tuned to 1,000+ whp with no low boost settings? And how are they shifted? 3rd gear tends to be the weak point in R154's at those VERY high power levels (again... highly expensive PGS gearsets are the only answer to that.. or a V160). Then there's the 1st gear thrust washer, front bearing retainer plate and not-overbuilt shift forks. Are you absolutely certain that the owners of both those cars didn't upgrade their R154's just to protect their investments? They sure did spend a lot of time perfecting the 7M's weaknesses. I'd find it hard to believe if they hadn't. That... or they have a spare R154 set aside in case it's needed. You can push 1000whp through them, sure. But the PROVEN safe long term limits for an R154 that's had internal strengthening is about 750whp. I'll be generous and say I've also seen 800-850whp quoted somewhere also. I prefer to go with the more conservative quote I've seen far more often.
Can you? Yes! And if you're lucky the R154 won't break. If you are so lucky, will your gearbox last nearly forever under those power levels like a V160 or Tremec TR6060? That has yet to be proven and so far the evidence says otherwise.
Is structural reliability up to 750-850whp not an impressive figure already for a transmission designed in 1986?
Look... this thread is turning into an argument rather than a healthy discussion about how to best adapt the R155. I have yet to see it proven that the gears are stronger (or weaker) than those in an R154 and I've not yet seen it proven that the weaknesses in all other R-series designs aren't inherent in this one. The less than ideal 1st-to-2nd gear spacing is something I'd like to see in practice.
^^ Still... those quibbles aside are minor to me considering what every other R-series is capable of well below 750whp.
supragt35, please, let's keep the discussion focused on the project you've taken on. I am interested to see where it goes. Even with the less than ideal gear spacing from 1st to 2nd I think it very well might be another option for SC owners if it doesn't require that much more modification than an MKIII R154 to bolt into our cars.
Last edited by KahnBB6; 01-21-16 at 04:22 PM.