How durable are the Q45 transmissions?

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#1 Sailor Scout
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How durable are the Q45 transmissions? Are there any weak points as far as life span, shifting quality, etc?


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Skibane
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The reliability started out pretty bad during the first few years (due mostly to a lack of adequate cooling), and quite a few transmissions were replaced under warranty. In the following years, reliability improved to the point where it was not uncommon to see 175K miles on a well-maintained transmission. Even so, the engine often outlasts the transmission by quite a bit. An aftermarket transmission cooler and top-quality synthetic ATF are recommended upgrades.

A lot of Q owners complain about a "lazy" 2-3 upshift, particularly until the fluid warms up to normal operating temperature. General consensus seems to be that the transmission is slightly undersized for the vehicle's weight and engine power.

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JATCO specs torque at 307 lb/ft which was equal to early engines. First gear start was rare until 1993 and reduced 1st and 2nd ratios in 1994 took more strain off.

Like ALL AT Brands, heat is the killer and summer slogs up hills ac on in 4th allowed alot to build up [because owners didn't downshift to 3rd [direct gear].


NightRiderQ45
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yeah I haven't had any issues with my transmission without a oil cooler. I've been changing my transmission fluid with a good Dex VI fluid every 15k to keep add pack and cooling to where it needs to be.

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Infinitiguy19
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#1 Sailor Scout wrote:How durable are the Q45 transmissions? Are there any weak points as far as life span, shifting quality, etc?
Do you want to put a Q45 transmission on a J30 or something?

I say Z32 (300ZX) 5 speed is the way to go with the VH if you want to unleash the power.

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Paul Wall wrote:
Do you want to put a Q45 transmission on a J30 or something?
Yes. I know it's all a dream right now, but I'm researching for my next project. Not trying to create a race car or a "pimp-mobile;" just improving in areas that leave a lot to be desired.
Paul Wall wrote:I say Z32 (300ZX) 5 speed is the way to go with the VH if you want to unleash the power.
Not doing an engine or transmission swap. But a good idea though for the other Q45 people.

Millennium'02-Q
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Paul Wall wrote:
Do you want to put a Q45 transmission on a J30 or something?

I say Z32 (300ZX) 5 speed is the way to go with the VH if you want to unleash the power.


Putting a 300ZX transmission in a Q (F50)?That would be sick! Has anyone put a manual transmission in a Q? I know, I should have searched...a little lazzy tonight.

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elwesso
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not sure why youd go from the RE4R03A vs the 01A.,.. You'd have to get a new driveshaft (the output splines are bigger on the Q trans).. torque converter and i'd imagine the flex plate are different...

5 speed swap in a J30 would be basically like doing it in a Q, except the trans actually bolts to the engine directly without a plate...


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