# Manual Transmission Swap 4sp to 5sp



## LECHEROGT (Oct 15, 2007)

Hey everyone. I have a 1988 Nissan Sentra (sedan) with a four speed manual transmission. I am in the process of installing a five speed. After I lined the transmission up with the engine, I noticed two of the mounts would not line up with the transmission (the mount to the rear of the engine and the one under the battery tray that mounts to the rear of the transmission). The five speed that I have was removed from a 1988 Nissan Sentra (sedan). I would like to know if all that I need to do is use the mounts from the donor car and if so will I be able to bolt the mounts to my car using the existing holes. 
I do not want to make any modifications. Any advice/suggestions will be greatly appreciated. If this is not worth the trouble, please let me know. Nothing is wrong with the four speed, just wanted the extra gear.


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## ahardb0dy (Nov 9, 2003)

I had a 5 speed swapped into my 90 that came with the 4 speed and my mechanic used all the original mounts but I saw on an autoparts web site that they list 2 different mounts depending on if the car has the 4 or 5 speed so I don't know what is up with that. If you have the 5 speed mounts and they are good I would try to use them and see if everything lines up correctly.

according to sentra.net the 5 speed from 82-87 is different than the 5 speed from 88-96, maybe the 5 speed you have is from a car that was produced in 87 and has the older style tranny, it may be different than the newer tranny, below is the tranny chart from sentra.net

Year(s) Model Transmission ID Type 
1982 Sentra RN3F01A 3 speed automatic 
1982 - 1986 Sentra RN4F30A 4 speed manual 
1982 - 1987 Sentra & Pulsar RS5F30A 5 speed manual 
1983 - 1993 Sentra & Pulsar RL3F01A 3 speed automatic 
1987 - 1993 Sentra RN4F31A 4 speed manual 
1988 - 1996 1.6L Sentra & Pulsar RS5F31A 5 speed manual 
1991 -1999 Sentra/200SX RL4F03A 4 speed automatic 
2000+ Sentra XE, GXE, & SE RE4F03B 4 speed automatic 
2000+ Sentra XE, GXE, & SE RS5F70A/V 5 speed manual


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## LECHEROGT (Oct 15, 2007)

LECHEROGT said:


> Hey everyone. I have a 1988 Nissan Sentra (sedan) with a four speed manual transmission. I am in the process of installing a five speed. After I lined the transmission up with the engine, I noticed two of the mounts would not line up with the transmission (the mount to the rear of the engine and the one under the battery tray that mounts to the rear of the transmission). The five speed that I have was removed from a 1988 Nissan Sentra (sedan). I would like to know if all that I need to do is use the mounts from the donor car and if so will I be able to bolt the mounts to my car using the existing holes.
> I do not want to make any modifications. Any advice/suggestions will be greatly appreciated. If this is not worth the trouble, please let me know. Nothing is wrong with the four speed, just wanted the extra gear.


Here is some additional information: My four speed transmission is a RN4F31A and the chassis is a B12.


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## LECHEROGT (Oct 15, 2007)

Hey Eveyone, I will have to eat my words. All the mounts were correct, but I did not have the transmission lined up exactly right. I took the transmission back out and re-installed it. Everything is back in and working fine so far. The extra gear seems to make a world of difference. ahardbody, thanks for the information on the transmission codes. I believe it would be safe to say if the four speed to be changed is code RN4F31A and the five speed is code RS5F31A then the swap should be no trouble. Hope this helps others that are contemplating the swap.


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## ahardb0dy (Nov 9, 2003)

your welcome, the one thing I'm wondering on mine is whether or not the speedometer gear that the cable screws into is a different ratio between the 4 and 5 speed. My 5 speed tranny that I used was brand new and didn't come with the gear so we used the one from the 4 speed.


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