another trans/radiator bypass done

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Bandy1080
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Postby Bandy1080 » Thu Oct 24, 2013 5:11 am

Interesting. Thanks for the data.

Do dealers perform the bypass or is it something that we have to do on our own? I live in the city with no access to a lift or anything.


skinny2
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Postby skinny2 » Thu Oct 24, 2013 6:59 am

Bandy1080 wrote:Interesting. Thanks for the data.

Do dealers perform the bypass or is it something that we have to do on our own? I live in the city with no access to a lift or anything.
I've never heard of a dealer doing this. In fact my buddy who is an expert mechanic said he wouldn't do it if I asked him to. Too much liability.

I would also be very concerned about performing the bypass if you have any warranty. This is a great way to get screwed if by chance the transmission fails for some other reason. I waited until I burned through the 100% coverage portion of the extended "radiator" warranty and then swapped radiators.

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NmexMAX
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Postby NmexMAX » Thu Oct 24, 2013 7:16 am

skinny2 wrote:
Bandy1080 wrote:Interesting. Thanks for the data.

Do dealers perform the bypass or is it something that we have to do on our own? I live in the city with no access to a lift or anything.
I've never heard of a dealer doing this. In fact my buddy who is an expert mechanic said he wouldn't do it if I asked him to. Too much liability.

I would also be very concerned about performing the bypass if you have any warranty. This is a great way to get screwed if by chance the transmission fails for some other reason. I waited until I burned through the 100% coverage portion of the extended "radiator" warranty and then swapped radiators.
This is true, the dealer would suggest a new radiator.

Also, the full warranty is up at 80k, hence why myself and doctah have decided to do this.

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doctahjones
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Postby doctahjones » Thu Oct 24, 2013 8:15 am

NmexMAX wrote:This is true, the dealer would suggest a new radiator.

Also, the full warranty is up at 80k, hence why myself and doctah have decided to do this.

i'm sure the dealer would too. and why wouldn't a mechanic buddy suggest doing the bypass? did he have specific reasons? all the shadetree guys i've talked to can't really think of a reason that the rad heat exchanger would be -required-, again going back to the coolant normally stays at 190, but trans stays at 150, and you can't 'cool' something with something that's hotter. now if you were towing and trans temps were above 190, then it starts to help, but for everyday type driving there doesn't seem to be a "good" reason for it.

i will probably eventually replace the radiator, especially if we ever get a travel trailer (in a few years). but i don't do any hauling (except haulin a$$! :P ) and since we still have the ext cooler in front of the rad, AND i have the bdgt to tell me trans temp i'm not compelled to swap radiators anytime soon.

skinny2
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Postby skinny2 » Thu Oct 24, 2013 8:31 am

doctahjones wrote:
i'm sure the dealer would too. and why wouldn't a mechanic buddy suggest doing the bypass? did he have specific reasons?
He's very particular about his work. Probably one of the best mechanics I've met and he generally only works on higher end cars. I've had him do some work for me on project vehicles and he won't cut any corners. He said it might never be an issue but in extreme situations it certainly could. Also he mentioned the radiator will cool the transmission fluid because the coolant at the bottom of the radiator is much cooler than at the top. So the coolant temps you're seeing are at the thermostat. I was planning to just do the bypass as well but after talking with him and really thinking about it...$400-$500 was cheap considering what's at stake. Plus there's no downside to a new radiaotor and fluid.

But his main reason he wouldn't do it for any old customer is liability. People just sue for everything so he doesn't like to bypass something the engineers designed from the start unless he happens to KNOW the modification improves upon that design. Considering the typical dealership....i'd fall over from surprise if they agreed to something like that.

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NmexMAX
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Postby NmexMAX » Thu Oct 24, 2013 3:36 pm

The VK56 has the t-stat up top, near the IM, but the ECT sensor is on the way bottom of the engine, south of the lower rad hose. Not sure of the VQ40.

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BigEz
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Re: another trans/radiator bypass done

Postby BigEz » Thu Oct 24, 2013 3:44 pm

doctahjones wrote: finally did mine, on a '08 5.6L, 81k miles.
Excelent post doctahjones. Used it to do mine today..http://www.thenissanpath.com/viewtopic. ... 0543#60543

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doctahjones
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Re: another trans/radiator bypass done

Postby doctahjones » Thu Oct 24, 2013 5:07 pm

BigEz wrote:Excelent post doctahjones. Used it to do mine today..http://www.thenissanpath.com/viewtopic. ... 0543#60543

cool deal. yeah i bet that was tons easier on a lift! and yeah the hardest part probably is taking off all the #$% bolts for the skid plate. not that they're hard, there's just alot of them!

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BigEz
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Postby BigEz » Thu Oct 24, 2013 5:29 pm

Yea, well worth the effort. I thought about adding an aftermarket trans cooler, but was limited on time today. I'll watch the trans temp for now, I can always add that later if needed.. connecting to the bypass.

Now I need to find a lube shop "I trust" to do a proper flush and fill. Although the fluid looked and smelled good with no sign of coolant... it was well used.

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doctahjones
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Postby doctahjones » Thu Oct 24, 2013 8:21 pm

i just changed my at 50-60k mi, along with both diffs and xfer case.....if i remember right. i'm at 81k now. will probably do tranny fluid again at 100-120k, just for piece of mind.

will also probably drain and fill my coolant at 100k, and brake fluid too. again, just for piece of mind.

Bandy1080
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Postby Bandy1080 » Tue Oct 29, 2013 7:14 am

Ended up having a stern talk with my service manager. He admitted that he had seen some 2008's come in with the transmission issues and a lot of them were out of warranty. I have an extended warranty until August so I told him I was really worried about what's going to happen after it expires. I have 81k on my 2008 LE right now.

This morning I brought the car in to get my timing chain replaced under warranty and he just called me and said that he found a leak in my radiator and has to replace it under warranty. Needless to say, I know that I don't have a leak since I flushed my coolant last week. I feel like I shouldn't be bragging about this, but good customer service is not dead. This dealership has definitely gotten a customer for life.

skinny2
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Postby skinny2 » Tue Oct 29, 2013 7:39 am

Good deal. It all just comes down to the dealer and what kind of people they have running shop. What brought up the need for the timing chain swap?

Bandy1080
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Postby Bandy1080 » Tue Oct 29, 2013 9:24 am

Was getting the coolant fluids flushed and apparently the chain was making some noise during their routine inspection. Its under warranty so I just agreed to have it replaced.

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eieio
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Postby eieio » Tue Oct 29, 2013 10:18 am

Bandy1080 wrote:Ended up having a stern talk with my service manager. He admitted that he had seen some 2008's come in with the transmission issues and a lot of them were out of warranty. I have an extended warranty until August so I told him I was really worried about what's going to happen after it expires. I have 81k on my 2008 LE right now.

This morning I brought the car in to get my timing chain replaced under warranty and he just called me and said that he found a leak in my radiator and has to replace it under warranty. Needless to say, I know that I don't have a leak since I flushed my coolant last week. I feel like I shouldn't be bragging about this, but good customer service is not dead. This dealership has definitely gotten a customer for life.
where did they say the radiator was leaking from?

wpgtibook
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Postby wpgtibook » Sat Nov 02, 2013 4:24 pm

Any folks here from the Canadian Prairies (Manitoba) that may be able to suggest a shop that could do the by-pass for me? I am having a bit of cold feet about doing this solo, given a few recent screw-ups on other brands. A bit "shy" these days to handle solo wrenching. PM if you have any suggestions or post here.


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