Whats up all. here's the story.
I have a 88 GXL and I have around 180,000 miles on
it. So I basically bought a 88 GTU. (it had been in a wreck, and has 54,000miles.) I can take anything I want from the car, here is my list to put on my car so far.
Engine, Tranny, ECU,
LSD, linkage (thought I might as well use it all.
Mirrors, Aero Pieces, tach showing 54,000 miles,
the struts & springs, the doors, and the carpet.
the car colors are identical inside and out.

If you have any other sugestions please
let me know, Thanks for your help.
Matt22

 

Basically, the difference between the GTU and GXL is that the GTU is a non-turbo no-frills, performance model. The GXL is a non-turbo luxury model with essentially the same brakes and drivetrain as the GTU.

The differences are mainly in the interior (different fabrics, sound system, convenience items, etc.). There are a few differences on the exterior. The GTU has an areo package that consists of a front air dam, small side skirts, and a rear spoiler. The GXL is low key in those terms, with the exception that a rear wiper was an option.

Make no mistake, the parts from the GTU are interchangeable with the GXL, so there should be no problems swapping parts from the wreck into the good car.

I suppose the only suggestion I'd have is use whatever parts you get from the GTU to replace any broken parts in the GXL, and sell what you don't need. Given the low miles on the GTU, those parts are probably in pretty good condition.

 

Hey thanks

 

actually the 88 GTU was kinda like an s5 GTUs...

 

Sorta the other way around....

a GTUs was like a 88 GTU which was a 86-87 Sport with Power mirrors, LSD and better carpet added.

 

ok i think there are some mistakes in here (if i am wrong please do correct me): The gxl does not come with the same brakes as the gtu the brakes the GTU comes with are the smaller brakes (or is this only on the s5 gtu?) The GXL came with the 4 piston brakes like the turbo models. And i believe the GXL comes with LSD also. Mark am i wrong on this one?

 

I was under the impressing that neither the 88GTU, GTUs, nor the Sport models had power anything. Anyone?

 

I dunno about the 86-88 GTU but my old 89 GTU had power mirrors.

 

The 88 GTU and all series 5 cars came in north america with power mirrors. Yep even the GTUs models.

Intresting that the GTUs also came stock with the heavy steel jack instead of the uderlichet alloy one found on the Sport and 88 GTU (and most of the other S4 cars).

 

Sorta wrong.

Okay, the basics again...

The 88 GTU has the same heavy duty suspension and brakes as the 86/87 Sport and S4 T2. It also came with the GXL's LSD.

The 89-90 GTU was the crappy base model, and should not be in anyway confused with the 88 GTU which was a sportier performance oriented model. The 89-90 GTU was the updated or series 5 verision of the series 4 SE or base models.

The 89-90 GTUs (note the small "s") was the updated or Series 5 version of the 88 GTU. The GTUs also had a LSD and a slightly differnet version of the heavy duty suspension and brakes.

As far as brakes these cars came with the heavy duty 4 piston front brakes (if it is not on this below list, it didn't come from the factory with the heavy duty light weight brakes):

86-87 Sport
86-90 GXL
87-91 T2
88-92 'vert
89-90 GTUs
91 coupe with GXL luxury package.

Note how the Base, Luxury coupe, SE, and 89-90 GTU are not on the list.

 

Watch out Icemark really knows his stuff.
One thing I must add, in the 88 rx7 brosure
they said the GTU comes with heavy-duty
disc brakes, and it says that the GXL comes
with High-performance disc brakes. and on
the last page it states that Heavy-duty disc brakes
were standard on the: GTU, GXL, Turbo, and the
Convertible. Just thought I would throw that in there.
lates matt22

 

how can you tell if a car has LSD? i happen to have a 91GXL. it was repainted, so i didnt really know what it was as far as model went. but i was asked if it had power windows, which it does, so i was told it a GXL. but as the car has 146K miles (only on the chassis), parts are changed around. is there an easy way to see if a car has LSD? thanks.

 

jack up the car at the pumpkin and see if both tires
spin while gently giving it some gas. lates Matt22.
oh and I believe but not positive but all series 5's
got the LSD except maybe the GTU. IT that right does someone else know more.

 

regarding checking the lsd, I may have this backwards but, if you jack the rear up and spin one of the tires, if the other wheel spins the oppiste direction then you have an lsd. I might have it wrong it might be if it spins the same way. do some searching and i'm sure you can find it. I would use this way instead os jacking it up and giving it gas. i'm a little too paranoid to do that.

 

that would be wrong

 

The 91 coupe with GXL package generally did not come with LSD. It was a factory option that only appeared in a few hundred cars. You will not have it if you do not have leather and power everything. And even if you do have factory leather and power everything doesn't mean that your car was equipped with a LSD.

The conventional method of testing a LSD (cranking a wheel around) won't work on the fluid type LSDs that the S5 cars had. There needs to be a prescribed amount of shear, before they engage.

 

No that is wrong. Almost no series 5 cars got LSD.

Only the 89-91 T2, the 89-90 GTUs and a few hundred of the 91 coupe with GXL package got a LSD

 

Oh, and the 88 GTU did come with power mirrors and many with a power sunroof, but the 89-91 GTUs did not come with a sunroof.

The GTU and later GTUs did not come with power locks or windows.

 

im wondering what's mine. i don't know if its a gxl or gtu. its a 90 white n/a. has power windows, power locks, sunroof, rear spoiler, blue cloth interior. any ideas icemark?

 

the gtus has no power and no sunroof and different gearing and the gxl has full power and sunroof

 

Simple LSD test (also a little bit of fun): Hold down the brakes, rev to 5k and drop the clutch. Then let go of the brakes and jump out and check it. 2 burn marks = lsd. 1 = no lsd.

 

I have an 88 GTU. It has 4 piston calipers, but I don't know how those brakes compare to the GXL's. Interestingly enough, this car also has the ribbed-looking tranny like the TII. My old GXL had a smooth case. It also has PW, PS and PB. It feels a LOT lighter than the GXL.

 

The brakes are the same on a 88 GTU as the GXL.

the tranny's are easily confused unless you know exactly what you are looking at. The real test would be if the bell housing and tranny are two parts or a single cast assembly.

 

well, i dont have leather (and i am thankful for that), and probably no LSD. i guess its cause i used to own a FF car, so i'm not used to the good traction. and my car is all stock as of now, so not a lot of power either. but just to satisfy myself, maybe i'll try the 5k drop. just for fun.

 

What is the difference in the Tranny's between the
GXL and the GTU which is better or more practical?
Lates Matt22
Icemark is the man!