FAQ: What transmissions swap into our Rivieras? ('97-99)

Abaddon wrote:

Gotchya covered.....

2 RPO codes are used for the 4T65E trans. RPO M15 is the "standard" trans, and RPO MN7 is the "heavy duty" version.

The heavy duty is only used in the supercharged versions of the 3.8L....Grand Prix, Monte Carlo, Riviera, Park Avenue, and I believe the V8 Aurora (and the rare SC LeSabre).

Here is a list of ALL the cars the 4T65E is used in.....

C body = Park Avenue
G body = Riviera and Aurora
H body = Bonneville, Olds Eighty Eight, LSS and Regency, Lesabre
W body = Grand Prix, Intrigue, Lumina, Monte Carlo and Regal

If you are going to take the trans out of one of these cars, check RPO code on the Service Replacement Transmission Assembly (SRTA) plate on the rear face of the trans to make sure what you are getting is the same. As far as the Internal Mode concern, I'll do some more digging later and post EXACT matches for our Rivieras.....I have to go put an oil sending unit in an Intrepid

I dimly recall some 3.5 or 3.8 Olds - were they Auroras or Intrigues?

Also, wasn't the Aurora v8 tranny the 4t80e?

Albertj

If the 3.5L Olds engines used 4T65e, was it the HD version?

I'm almost certain the Aurora V8 used 4t80e.

You are right, the Aurora uses the 4T80E (RPO MH1). The Intrigue uses a 4T60E (RPO M13) and a 4T65E....one for the 3.5L and one for the 3.8L. Again identified by the SRTA plate. I will still post all my findings about a swap tomorrow.

After looking and finding all the 4T65E HD applications, there are 4 different gear ratios available for the trans, all of which are still RPO MN7. I will have to get a hold of my buddy at the Chevy dealer and cross reference the part numbers to get exact matches. It'd be sweet to get a drop-in tranny with a 3:29 ratio as our Riv's are 2:93.

UPDATE.....I currently have 22 P/N's for all the 4T65E HD applications ranging from 1996 to 2001 for all different models. I didn't like my findings, as the numbers changed throughout the years/models, which was expected.

I am currently getting all the P/N's for the trans CASE. I think the case P/N's will be more helpful on trans swaps as it's the overall shape/mounting that we need to be mostly concerned about.

If I don't like my findings there (btw it's turning out nicely), I'll move on to the gear sets......

I'm "married" to this thread now......bear with me, the next post is more than likely to be LOOONNNGG, yet informative

Well, after hours of staring at P/N's for all different GM models ranging from 1996 to 2001, the transmission swap still has some ?'s to be answered. Guess I'll start typing and see how it goes.....
*NOTE* all of this info is regarding S/C cars

1996 Riv trans...P/N 19125050 shares possibly with the PA. The PA lists 3 different P/N's depending on options (which I couldn't find).

1997 Riv trans...P/N 89059825 shows that it IS the same trans as the 1997 PAU, however when you look up a '97 PAU, it lists 89059827, which has a notation *all 1997 Buick and Pontiac w/Supercharger. This raises some questions. I looked up 1997 Grand Prix and Regal GS to confirm P/N 89059827, which leads us to believe that a PAU, Riviera, and GP trans in 1997 are the same with different P/N's? .

1998 Riv trans...P/N 89059831 is the same as the 1998 PAU. I confirmed this by looking up a 1998 PAU. When looking up a 1998 Grand Prix, I got P/N 89059835, which is listed as *all 1998 Buick and Pontiac w/Supercharger. Confirmed 89059835 for 1998 and 1999 Regal GS. Why does it say "all models but list the Riv and PAU with a different P/N?

1999 Riv trans...P/N 89059840 had no notations and didn't list applications, which to me is inconclusive. The 1999 PAU P/N 89059839 shares it's trans with no other cars.

I won't get into the 2000's, as the trans numbers are WAYYY different and share nothing as I can see with our Riv's.



As for the trans cases.....

P/N 24217187 is for the following,
1997-1998 Riviera
1997-1998 PAU
1997-1998 Grand Prix GTP
1997-1998 Regal GS

P/N 24217184 is for the following,
1999 Riviera
1999-2000 Grand Prix GTP
1999-Regal GS

The 1999 PAU P/N 24217185 shares nothing, as with the entire trans. Leads me to believe that the Internal Mode Switch has something to do with this?

Looks to me, according to the case P/N's, that the transmissions (cases) for the cars listed under the P/N's should be interchangeable, aside from the 1999 PAU. It appears that the transmission P/N's have something to do with the year of the vehicle, as they change correspondingly. This may turn out to be all smoke and mirrors, but who knows. I'll have to get into internal and electrical P/N's to dig up some more. I'm hoping that any of this is helpful, as I will continue to contact certain aquaintances to get better answers

I can verify firsthand that some GTPs do NOT have the correct case to fit our cars. The case does not have the correct webbing cast into the rear to support the rear trans mount. I put one of these into my '98 and cracked the housing open on the first shift. We believe the transmission was from a '97 GTP but cannot confirm as we didn't keep the broken case.

Look at the pictures in this thread for more about my firsthand problems with the case mismatch: https://rivperformance.editboard.com/series-ii-engine-transmission-f4/identify-this-part-t2090.htm

Looks like (according to the trans P/N's), that the only "drop in" trans would be 1997 PAU and Riv, and 1998 PAU and Riv, the 99 is different. I wonder why the case #'s are the same if they are in fact different?

Have the GTP and Riviera case numbers actually been identified first hand, or is it your reference source that could be incorrect? I only ask because of the inconsistencies you found with the part numbers fitting Riv, PA, GTP, and GS - we already know this not to be correct because of Derek's (and others') experiences.

The part numbers I have listed are all GM numbers. When you look up the year, make, model for the case #, those were the only 3 P/N's that listed, and are apparently year specific (a '99 won't work on a '98). Look up a '98 GP and you get 24217187, look up a '98 Riv and you get the same number. Now if you look up a '98 transmission assembly you get 89059831, which is the same as a same year PAU. The GP lists a different trans assembly P/N, but the same case P/N. The RPO code for the 4T65E-HD does not change (MN7) for any year, as it's just the trans ID. So going by that alone is not enough.

In Derek's case, it very well could have been a case from a GT non-supercharged. In fact, I just looked up a GP GT....a non-S/C trans case is P/N 24211898, and the S/C car P/N is still 24217187, which matches ours. At least now we have some sort of reference to compare P/N's to. I'm sure there will be some more "wtf's" in the future regarding this issue. The Riv unfortunately shares it's platform with only 1 other car, and we can't even take parts from that .

If we are going to attempt trans swaps, we should make sure that all the info on the SRTA plate is the same.

It's as simple as this: Will the 4T65E or HD bolt right into a 96 Riviera? or are there some modifications that need to be made?

modifications need to be made.
As far as bolt patterns, i dont know for sure. I do know you will need to swap PCM's with the 4T65E riviera. The new trans really should be from a riv to make sure the rear mount webbing is the same.
You would also need to run the wires from the new trans to the new PCM.

I am trying to do the research on this stuff myself too bc i need a rebuild ASAP. Aaron will probably merge this with the other thread btw.

4T60E has a 245mm torque converter. 4T65E has a 258mm converter. Can the "upgraded 245's work in the 4T60? i dont know yet.

The 4T60E in the riv is an HD trans but i dont know how many hard parts are interchangeable or upgradable.

the only reason i see to swap it over is to have more control with a tuning program of the trans and to make finding upgraded parts easier.

Well this brings up another question, How much HP and torque can the 4T60E reliably withstand?

im pushing 400+ ft-lb torque through mine and im just starting to have problems.
A really old member (camlifter) had a 96 with N2O and it was running 12.9's. i dont recall him having anything special done to it.
Maybe im an outlier, but from what i have been noticing the 96's have the least amount of failures statistically. Maybe because there are more 97-99's out there, or maybe b/c they mod more than 96's IDK.

Mr.Riviera wrote:

im pushing 400+ ft-lb torque through mine and im just starting to have problems.
A really old member (camlifter) had a 96 with N2O and it was running 12.9's. i dont recall him having anything special done to it.
Maybe im an outlier, but from what i have been noticing the 96's have the least amount of failures statistically. Maybe because there are more 97-99's out there, or maybe b/c they mod more than 96's IDK.

Thats good to know because im thinking about putting a healthy dose of the bottle on my Riv. I guess we'll see what happens

I have 98riv sc blk all stock. Intermittant p0341 code also trans downshifts at stoplight and studders in overdrive after hot. Also have 96 riv sc for parts, good eng and trans. Just found out 96 and 98 trans not the same. Will trans from 98 or 99 boniville sc swap to 98 riv. Also 96riv to98 riv engine. Thanks

has anyone thought about swapping a manual trans into our cars?

Abaddon wrote:

AA wrote:

Does anyone know if a '99 PA Ultra transmission will fit and connect correctly into a '98 Riviera? I heard there was a change in '99, they went to the internal mode switch. To make work, you are supposed to repin some plugs on your harness. Can anyone validate this info?

Thx,
AA

PS - what does "internal mode" mean, anyway?

The '98 Riviera (G body) trans uses a PNP switch which is integral to the trans. It's powered by Ignition voltage directly, goes through the stop lamp switch, and then on to the shift interlock solenoid. This means that in order to get the car out of park, the tail lamp (brake) circuit must be "completed" in order for the Shift Interlock Solenoid to disengage allowing the shift out of Park.

The '99 Park Avenue Ultra (C body) uses what they call an Internal Mode Switch which basically is a module in itself. Instead of being powered by Ignition Voltage, it is connected to the PCM and BCM via Class II serial data lines. The Auto Trans Shift Interlock Solenoid (notice the name change) is on a completely different circuit, yet controlled by the BCM. On that circuit, the PA utilizes a Lamp Control Module (Park Gear Input), a Stop Lamp/Auto Trans Shift Lock Control Switch (which opens when the brake pedal is pushed), and then on to an Auto Trans Shift Lock Solenoid.

In a nutshell, the '98 Riviera uses only the PCM to help control the trans.
The '99 PAU uses the PCM to control the Internal Mode Switch, and the BCM to control Shift Interlock system.......2 completely different systems as far as communications and solenoids/switches are concerned.

The plugs and harness into the 2 transmissions ARE different, although both 20 pin connectors, the setup is different and will not plug into each other as different wires go different places. I've been staring at the complete 4T65E trans schematics for both the Riv and the Park for about an hour now. Without posting both GI-NORMOUS schematics for you to see, that's about all I can tell you. If you want to know more.....ask and thou shalt recieve

Up from the past!
Great info, I have a 99 Park Ultra and the junkyard says a 99 Riv tranny lists as a fit.
But - it has a switch on the trans controlled by the shift cable - sounds like the mismatch you decribe above.

Is their ANY other car model, or year - that will direct fit a 99 PAU?
Can I look for a newer year PAU tranny? I hear some of the weaker internals from the late 90's were upgraded by GM in early 2000's cars....but, will it bolt in AND be wiring/PCM compatible?
Thanks - and great website - you guys dig deep for your info! .

The 'weaker internals' were upgraded in '97-'98 when they changed from the -60 to the -65 transmission. The -65 was used for many years after that. There is a thread around describing where the rear transmission mount attaches - that's the only casing difference you need to watch out for. Some W-body cars did not get the case that has all the reinforcements for the rear mount that the G-bodies use. Otherwise the internals are the same, besides what you see noted above. I'm not sure what years (or if ever) they started matching up the internal/external modes. I would suspect you should be okay with a '00 - '02 PAU trans, but don't buy one based on my loose speculation!

Got a low mileage used trans out of a wrecked PA. Got mine pulled out, was fitting up the new trans everything slid in perfectly tightening down the bellhousing bolts and I heard a pop, crack was along all three top bellhousing bolt holes. So the case is done, how hard is it to swap internals

Are you absolutely sure it came from a PA, as in you saw the car it came from?

Any pics of the broken case?

Nope did not see the car, webbing for the mounts all lined up. Only difference I could see was mine read 901s and the PA Trans read 905X After I saw the crack tools went in the garage packed in my hoist I'm done with this thing for the day.